*Wf; #VWtf^*«v'"^.;<ft
f.^|»^^
I^\vt8
*■>.••'
;iee ^v
^tiiv^
\^>'>>'.^
^
M>
•^
^c>:&;
:»f,(e\r
Dc«t
M^.'e,
Mi
'U;^'
<&

Vfc'*l&

bx*
«3
■$vv
^>/v^>:
rH^^&vv-^

%
D;/
 
u
%i-L J
A /W
0 ilLUty'
q£^. M  9uU*.
s 
£*^
^»
■^
•v^,.

Sv

^C-
V\
—s
rr>
i  *

,^t™X(—^ 
e\
^
y


^

^ ^J \.

K i
r>.
d
^P
M 
•y't ^
0m
7jaI
tt- ?- ■( ■ *  -
l-#l
•4*A-
"KJ
f*,
ry 
L 
ELEMENTARY
ANATOMY AND PHYSIOLOGY,
FOR COLLEGES, ACADEMIES,


    AND OTHER SCHOOLS.
EDWARD HITCHCOCK, D. D.,LL. D..,
        I u

            AND

    EDWARD HITCHCOCK, JR., MD.,
     PEOFE88OR8 IN AMBBBBT COHE«t,



         REVISED  EDITION.



   NEW YOEK • : • CINCINNATI • : • CHICAGO

  AMERICAN  BOOK COMPANY 
          Entered, according to Act of Congress, in the year 18C0, by
                      IVISON &  PH1NNE f,
Ic tho  Jerk's Office of the District Couri tor the Southern District of New York.
M.  I

■^ 
PREFACE.
  This work  is offered to the public in the hope that it has
some desirable features as a text-book, not found in any of the
able elementary works on Anatomy and Physiology now ex-
tant.   One is, the  introduction of more of microscopic anat-
omy than  is usual.  Another is, a large addition  on Com-
parative  Anatomy,  which is  now become a science of great
importance.  A third is, the  Religious Applications of these
sciences ; which, although all will acknowledge  to be emi-
nently appropriate,  we have found in no elementary  treatise;
  We  make no pretensions  to distinguished attainments or
reputation  in these sciences, as a reason for writing this book.
But both of us have for a great number of years  been in the
habit of hearing recitations and giving lectures upon them in
the College and the Academy, and we ought to know what
sort of a text-book is needed.   But we dare not boast that we
have come  up  to our ideal.  We have tried to give  a condensed
yet clear exhibition of the leading principles and facts, which
are detailed in such works as  Carpenter's Human Physiology.
his  Comparative Physiology,  Hassall's Microscopic Anatomy,
Griffith  and Henfrey's Micrographic Dictionary,  Peaslee'
Histology,  Todd and Bowman's Physiological Anatomy, Wil-
son's and Gray's Anatomy, Draper's, Dunglinson's, and Dal-
ton's Physiologies, Van Der  Hoeven's Z oology, and the works
of Cavier,  Owen,  Agassiz, Wyman, Leidy,  and  Wagner on
Comparative Anatomy. 
IV
PREFACE.
   Through the liberality of the publishers we are able to pre-
sent unusually full illustrations of subjects, which could other-
wise be only imperfectly comprehended by the learner.
   Many of  the  drawings  contain  more  minute  details of
the parts represented than are described in the text.   The in-
structor can require  these to be recited or not, as  he pleases,
according to the  age and ability of the pupil.   So as to the
parts on Comparative Anatomy, as they are distinctly sepa-
rated from the rest,  they can, if desired, be passed  over in re-
citation.
   At the earnest solicitation of my son, my  name  stands first
on the title-page.  But justice requires me to state that most
of the body of the work  has been prepared by him.  I have
supposed it most appropriate that it should be so, since he has,
and I have not,  passed regularly through the medical school.
Yet perhaps the public may have some confidence in my judg-
ment as a teacher for more  than forty  years, in shaping  the
materials so as to be best adapted for purposes of instruction.
But aware, in some measure, of our deficiencies and imperfec-
tions, neither  of us,  in sending forth the work,  feels it to be
beyond criticism and improvement.   In a field so wide, where
so many are pushing their investigations,  and the  highest
authorities  so frequently change their  views, we do  not  ex-
pect  to avoid all  mistakes;  but in our  successive  editions,
we shall correct all errors which we find, and try to incorpor*
ate the new discoveries.
                                  Edward Hitchcock.
  Amherst College July, 1860. 
CONTENTS.
Preluiinary Definitions and Prwciples.......................   5

                     CHAPTER  I.
Osteology and  Syndesmology — Descrdption of the Bones and
      Ligaments..............................................  31

                    CHAPTER  II.
Myology—Description of the Muscles......................... 101

                   CHAPTER   III.
Splanchnology—Description of the Digestive Organs...........155

                    CHAPTER  IV.
Angiology—Description of the  Heart, Blood, and Blood-Vessels. 201

                     CHAPTER  V.
Pneumonology—Description of  the Organs of BREATmNG........ 2A

                    CHAPTER  VI.
Ichorology—Description of the Organs of Secretion..........282 
vl
CONTENTS.
                  CHAPTER  VII.
                                                         PAGE
Neurology—Descrdption of the Brain and Nerves.............316



                 CHAPTER  VIII.

1£he Inlets to the Soul—The Senses.........................t 361



                   CHAPTER  IX.

Religious Inferences from Anatomy and Physiology..........., 420 
PRELIMINARY
DEFINITIONS   AND  PRINCIPLES.
  1. All the objects in the material world are divided  into
Organic and Inorganic.
  2. Cells, Membranes,  and Fibers.—In organic bodies, the
matter composing them is arranged in the form of cells, mem-
branes, and fibers, variously combined.   In  inorganic bodies,
though  the  particles  are often arranged with mathematical
precision in particular modes, cells, membranes,  and fibers
are  not formed.
  3. Life.—The principle of life is always associated with or-
ganic, but never with inorganic bodies.
  4. Examples  of Organic  and  Inorganic Objects.—Or-
ganic bodies embrace Animals and Plants ; every thing else in
the  material world is inorganic, as, air, water, minerals, rocks,
and soils.
  5. Man the  Head of  the Animal  Kingdom.—"Man is
the  end  toward which all the animal  kingdom has tended
from the first appearance of the Palaeozoic fishes."—Agassiz
and Gould.
  6. Anatomy and Physiology.—Anatomy is the science that
 Questions. 1 Give the two kingdoms of the material world.  2 What is the arrange-
ment of matter in organic and inorganic bodies? 8  With  which is life associated?
4 State some examples of organic  and inorganic bodies. 5. Why is man placed at the
head  of the animal kingdom ? 6. Define Anatomy. 
6
HITCHCOCK'S  ANATOMY
describes the different organs of animals. Physiology describes
their functions, or uses.  If  the organs of man  alone be de-
scribed, the science is called Human Anatomy and Physiology.
If the description embrace the lower animals, it is called Com-
parative Anatomy and Physiology.
   7.  Another  definition of Anatomy, is the science of Organ-
ization ;  and of Physiology, the science of Life.
   8.  Animal  and Vegetable  Anatomy and  Physiology.—
There are  also  such  sciences  as  Vegetable Anatomy  and
Physiology.  Indeed, there is  a  strong analogy between the
organs of plants and animals, and their uses.   Nor is it easy
always  to draw the  line  between plants and animals, where
they approach the nearest to each other.
   9.  Intimate  Connection  of  Anatomy and  Physiology.—
Few writers confine  themselves to  the structure of animals,
when treating of their anatomy, but treat also of the function
of their organs; and the same thing is still more generally
true  of writers on physiology.   We do  not  separate  these
6ciences in this treatise.
   10. Fifteen  Chemical  Elements in the  IIumanBody.—Of
the sixty-five  chemical elements or simple  bodies  known to
exist, only fifteen have been found  as  normal  constituents of
the human body.  The following is the list:—

    1. Oxygen,           6. Phosphorus,         11. Chlorine,
    2. Hydrogen,          7. Calcium,            12. Fluorine,
    3. Carbon,            8. Magnesium,         13. Silicon,
    4. Nitrogen,          9. Sodium,            ]4. Iron
    5. Sulphur,           10. Potassium,          15.  Manganese.

   11. Carbon,  Hydrogen, Oxygen,  and Nitrogen.—The first
three of the above elements are found in all the solids and fluids
of the body, without  exception.  The first four occur in all the
  What is Physiology ? When is the term comparative applied? 7. Give a more con-
cise definition of Anatomy and Physiology. S. Describe animal and vegetable Phy-
siology. 9. Speak of the close relationship  between Anatomy and  Physiology.  State
the whole number of  chemical Elements  10 State those which are found in the human
body.  11. Where are the first three found? Nitrogen also?
t 
AND  PHYSIOLOGY.
1
solid parts, and in all the fluids except fat.   They form the
chief and most important ingredients in animals and plants.
   12.  Sulphur and Phosphorus, Magnesium, Sodium,  Pot-
assium, Chlorine, Fluorine,  Calcium,  Silicon,  Iron,  Man-
ganese.—With scarcely an exception, these elements exist  in
the body as compounds; that is,  two  or  more of them are
combined,  as  in water,  in oxyds,  and in various salts.    Sul-
phur and phosphorus exist in albumen and fibrine, as well  as
in the brain,  about  i^th  of its  weight being phosphorus.
Bones are more than half made up of Phosphate of Lime, and
they  contain a  small per cent, of Phosphate of Magnesia.
Sodium, in the form of a chlorid  (common  salt), is found  in
every  solid and fluid of the  body.   Potassium occurs as  a
chlorid in the  muscles,  and aj an  oxyd  in salts.   Chlorine
forms  chlorohydric acid by combining with hydrogen  in the
gastric juice.  Fluorine exists in the bones in a minute quan-
tity, combined with calcium.   Silicon is found in small quan-
tities in hair, wool, and feathers, as  silica.    Iron forms  about
the 2000th part of the blood, and it  exist3  also in-the muscles,
hair, and milk.  Manganese, in  small quantities, has  been
detected in bone, and perhaps in the hair.
   13. Copper, Lead, and Arsenic.—Copper, lead,  and arsenic
have been detected in minute quantity in human flesh.   But
it is not probable that they are normal constituents.
   14. Inferences.—From these facts we  learn that our food
and drink should contain the fifteen ingredients above described.
Milk and eggs are the only articles  that do contain them all;
and hence, the importance of variety in diet.  And the fact
that we are obliged to use ten mineral ingredients  in our food,
 shows the absurdity of a prevalent prejudice that no miners.1
 should ever be taken as a medicine.
   15.  Immediate Principles.—As they exist in the body, the
   12 state in what organs Sulphur and Phosphorus are found.  What is one of the prin-
 cipal ingredients of bones ?  Where is Chlorine found ?  Fluorine ?  Silicon ?  In what
 noita of the body is Iron found? IS.  What is to be said of Copper, Lead and Anenicl
 14. What should our food contain ? Are mineral ingredients always poisonous?  15. De-
 fine Immediate Principles. 
8             HITCHCOCK'S  ANATOMY

fifteen elements above described form a large number of con>
pounds,  called Immediate Principles,  or Organic  Radicals.
They exist naturally, and can be  separated anatomically, that
is, mechanically,  from one another;  but the divisions can be
carried no further without chemical decomposition.  A few
elementary substances found in the system, as, oxygen, hydro-
gen, and nitrogen, are sometimes  called Immediate Principles.

  16.  Immediate Principles  Chemically Grouped.—We are
certain that eighty-four of these principles have been found in
the human system.  If we group them according to their chem-
ical  characters,  they will fall into  the following  divisions.
Half of them are the result of the waste or metamorphosis of
the substance of the body ; the other half exist independently
of any such change.
  1.  Gaseous, and not  saline: Oxygen, Hydrogen, Nitro-
gen, Carbonic Acid, and Water.
  2.  Salts:  Chlorids (2), Fluoride  of Calcium, Ilydrochlo-
rate of Ammonia, Carbonates (4), Bicarbonate of Soda, Sul-
phates (3>, Phosphates (7), Lactates (3),  Oxalate of  Lime,
Urates (5),  Hippurates (3),  Inosate of Potassa,  Pneumate
of Soda, Taurochlorate of  Soda,  Hyocholinate  of Soda, Gly-
cocholate of Soda, Oleate of Soda, Margarate of Soda, Stear-
ate  of  Soda,  Caproate of Potassa, Soda,  &c.
  3. Acids:  Lactic, Uric, Hippuric, Pneumic,  Lithofallic,
Margaric, and Stearic.
  4.  Neutral Nitrogenous  Compounds:  Creatine,  Urea,
Cystine, and  Creatinine.
  5. Neutral Non-Nitrogenous  Compounds:  Sugar  from
the Liver, and Sugar of Milk.
  6. Fatty  and  Saponaceous  Compounds :  Cholesterine,
Oleic Acid, Stearic  Acid,  Oleine, Stearine, &c. (13.)
  7.  Coagulable Principles: Fibrine, Albumen,  Caseine,
Globuline, Musculine, Osteine, Keratine, Hematine,  &c.  (18.)
 16. State the number of these principles that have been already found. What are
one half of them derived from?  Give the first group, or the gaseous ones. State th»
Baits. The Acids.  The 4th, 5th, 6th and 7th classes. 
AND PHYSIOLOGY.
9
  17.   Immediate  Principles Physiologically Grouped.—
If we group the preceding substances according to their phy-
siological relations, we might, with Dr. Carpenter, bring them
all into  four divisions.
  1. Histogenetic Substances, or such as are converted into
animal substances, and are nitrogenous.
  2. Calorific Substances, mainly intended  to produce heat,
and are non-nitrogenous, as, sugar and oils.
  3.  The components of the living animal substance.
  4. Excrement it ious  Substances, formed  within the body,
and thrown out of it.
  18. Other Probable Principles.—Quite a number of other
substances have been detected in the human system, which
some regard as immediate principles.   But it is safer to wait
till further examination has removed doubt.
  19.  Several of the above principles are capable of crystal-
lization, and are some-
times found in that state
in the  body.   Figs. 1
and 2  show  two exam-
ples  of these  crystals,
the  first  of  Hippuric
acid, and  the   other of
Creatine.
  20. To go into minute
details respecting the im-
mediate principles above
described, would occupy
too much space in a work
like the present.   But a
few statements  respect-
ing  the  most   import-
Fm. l.
 17. What are the Groups of these substances when physiologically eronped ?  Who il
the authority for this ? Define the Histogenetic and the Calorific group. What are ex-
creuientitious substances ? Are there any other principles in the body ?
                             1* 
10
HITCHCOCK'S  ANATOMY
                                     ant of them seem desir-
                                     able.
                                        21.  Oxygen.—Oxy-
                                     gen  is  regarded  as  an
                                     immediate principle only
                                     when it exists in  a free
                                     state, as  it does  in the
                                     blood,  which,  in   ah
                                     adult,  contains  sixty -
                                     one  grains:   nine  and
                                     a  half  cubic  inches be-
                                     ing;  found  in the  arte-
                                     rial, and  fourteen and a
                                     half in  the venous blood.
An adult consumes in a year about eight hundred  pounds of
oxygen.   An inhabitant of  a mountainous region 18,000 feet
above the sea (in Potosi) consumes, however, only two thirds
as much as  one upon the sea-shore.
   22. Hydrogen and  Nitrogen.—Hydrogen  is  found in a free
state in  the  stomach and  some  parts  of the  intestines, and
nitrogen in  the lungs, blood, and intestines.
   23.  Carbonic Acid.—Carbonic acid is found in the lungs,
the alimentary canal,  the blood, and urine.
   24.  Water; Cubical  Size of the Body.—Water enters into
the  composition of every fluid, and  every solid  in  the  body.
The bulk of the body, upon an average, is equal to  a cube of a
little more  than  sixteen inches on a side ; and the amount of
water equals a cube  a  little more  than fourteen inches on a
side, or nearly three fourths of the body.   Every  part, ex-
cept bone,  enamel, teeth, tendon, dry cuticle, and  elastic tis-
sue, is  more than half water.
  21. How much Oxyiren by weight is found in the body? What bulk of oxygen is found
In the venous and what in the arterial Mood ?  How much does an  adult consume by re-
spiration and otherwise in a year? What effect does elevation above the sea have upon
the amount consumed? 22. State how Hydrogen and Nitrogen are found.  23. Carbonic
acid also.  24 How important a constituent is water?   Give the  size of the body if re-
duced to a cube. If this cube were water, how large would it be ?
 
AND PHYSIOLOGY.
11
   25.  Amount of Water Consumed Yearly by  an Adult.—
An adult drinks about fifteen hundred pounds of water yearly;
and throws off" through the various waste-gates nineteen hun-
dred pounds.   The difficulty of accounting for  the four, hun-
dred pounds has led some to suppose that water is formed in
the system by the union of oxygen and hydrogen.
   26.  Common Salt in  the Body.—The salts that have been
enumerated, are found in almost every part of the body.  Com-
mon salt (Chlorid of Sodium) is found in every fluid and solid,
except enamel.   The whole amount in man is 277  grains.   It
subserves many important uses.
   27.   Carbonate  and  Phosphate of Lime, &c.—Carbonate
of lime  exists in considerable quantity in the bones,  along
with a much larger  quantity of the phosphate of lime, and  a
small  amount  of phosphate  of magnesia, and of fluoride of
calcium.  These salts, except  the fluoride, are found  in most
other parts of  the body.
   28.  Acids, Salts, &C.—Most of the acids and salts, the neu-
tral nitrogenous compounds, the sugars, the fatty and sapona-
ceous  compounds, exist, or are formed  in the  fluids of the
body, and though numerous (forty-two in all),  their quantity
is comparatively small.  They are mostly formed by disassimi-
lation  in the body, and hence only  their elements  need to
exist in our food.
   29.  Sugar in  the Body.—Only two kinds of sugar exist, or
are formed in  animals.   Grape sugar is found in the liver, in
some of the veins, and  other  organs.   In the disease  called
Diabetes, its quantity is very much increased, and, in fact, an
excess of sugar in the system is a sign of serious derangement.;
   30. Fats in the  Body.—The fatty principles, cholesterine;
oleine, etc., exist in the body in cells, in chemical combina-
  25. How much -water does a man consume in a year?  How much is thrown off during
the same time ? Explain the reason.  26. Where does common salt occur in the body?
How many grains exist in the body ?  27.  la what parts of the body do Carbonate and
Phosphate of Lime occur ?  28. How many acids and salts are found ?  State how they
are formed.  29. How many kinds of sugar are found in animals?  What does an excesj
of sugar indicate ? 30. How do the fats occur in the body ?
i 
12            HITCHCOCK'S   ANATOMY

tion with other  substances, and  as oil  drops or fat globules
not inclosed.  These principles are mostly taken as food into
the system, but they are  most  probably also  formed  there
from  elements;  certainly, the  liver  has this  power.  One
tenth of the brain is composed of fat; and it  is only in tho
last stages of emaciation, that this supply is exhausted.
   31.  Assimilation  Necessary.—The principles  thus far de-
scribed, constitute but a small proportion of the animal frame.
'But the organic, or  coagulable  principles,  enter  largely into
its  composition.  Indeed, they  form the principal source of
nourishment.   The most important of these principles (albu-
men, fibrine, and caseine) are in  a  fluid state  in the body;
the others are solid, or demisolid.  Though the materials for
their formation must exist  in the food, yet there is  reason to
Buppose that the process of assimilation is necessary, to trans-
form them into these principles.
   32.   Albumen, Albuminose,  Caseinf.—Coagulation  takes
place when a liquid, or semi-liquid, passes into a solid  state.
The white of an egg gives a  good idea of one kind of albumen
(ovalbumen).   Seralbumen exists in the blood, and in  other
liquids of  the body.  Albuminose is found  in the same fluids,
and has been, till of late, confounded with albumen.   It  is
formed  in the upper intestines, but when it passes into the
blood,   it  becomes  mostly  albumen,   sometimes  musculine,
fibrine,  etc.  Animal caseine is  found only in  milk, being
most abundant when an  animal diet is used.  It contains from
four to  six  per cent,  of  phosphate of lime,  and  hence the im-
portance of milk for  young animals, that their bones may be
developed.
   33. Fibrine,  Musculine, Globulinc, Ostcinc, and Gluten.—.
Fibrine is found in the blood, and when it coagulates, the mass
ii fibrous,  the process being called fibrillation.  It is this  prin-
ciple chiefly that causes blood  to coagulate, the great importance
  Is fat formed in the body, or taken in from the food? 31.  State  the three most im.
portant organic principles. 32. Define coagulation. What is ovalbumen, seralbumen and
albuminose ?  In what is caseine found ? What important ingredient does it contain 1
83. Where is fibrine found ? What causes coagulation of the blood ? What practical bene.
dt is derived from coagulation ? 
                  AND  PHYSIOLOGY.                13

of which in arresting dangerous  hemorrhages is well known.
Coagulation appears to be a vital process, that is, dependent on
life for its  development, and not on chemical laws only. It can
be prevented by any thing that destroys life, such as  poisons,
or a temperature too high, or too low.   Fibrine does not exist
in the muscles.  That which  has been called such is muscn-
line, which is endowed with the vital property called contractil-
ity.   Globuline occurs only in the red corpuscles of the blood.
Osteine  is the substance from which  gluten  is made, by the
action of boiling water, for gluten does not naturally exist in
the body.   Osteine is the essential organic element in bone.
   34. Ilematine___Hema-
tine is the coloring matter
of the blood,  and though
iron  is  found  in  connec-
tion  with  it, all  the iron
can be abstracted without
destroying    the    color.
Hence,  that  can not de-
pend  on  the  iron.   He-
matine  is probably pro-
duced  from   certain  red
crystals, occurring in the
red corpuscles.   A group
of these  crystals  is here
shown.
   35.  Proteine Compounds.—All the organic or  coagulablf
principles contain nitrogen,  or  rather, are  composed  essen-
tially of oxygen, hydrogen, carbon and nitrogen.  Hence, their
value as food, since a greater part of  the body is composed of
 these elements.   Albumen,  fibrine,  and  caseine have been
 termed  Proteine Compounds, for they can easily be changed
   Is fibrine found in muscular tissue * What is the proximate principle of muscular tis-
 sue »  Where does globuline and osteine  occur ?  34.  What is the coloring matter of the
 blood? Has iron any thing to do with its color? What is the Ilematine produced from ?
 35. What four simple elements make up  all the organic principles? Why are albumen.
 etc., termed Proteine compounds?
Fig. 3.
J 
14            HITCHCOCK'S  A X A T O M Y

into Proteine, a substance,  however,  which does  not exist in
nature,  but results  from the decomposition of the  principles
above named.


                    HISTOLOGY.

   36.   Organic  and  Inorganic  Structure.—Animals  and
plants have a  structure different from  that of minerals when
we examine them with the microscope.   The former is called
Organic, and the latter Inorganic Structure.
   37. Vitality tiie  Cause of Organization.—Vitality, or the
principle of life,  or  the Vital Force, is the  cause  of organi-
zation.   The nature of life is indeed involved in obscurity;  but
its effects are manifest, and among them is organization :  al-
though  some have maintained, but without good  reason, that
the vital force is  nothing but a peculiar manifestation of heat,
mechanical force, chemical action, galvanism, etc.
   38. Elementary and Primary Tissue.—The simplest forms
of organized structure are three.
   1. Simple Membrane.
   2. Simple Fiber.
   3. Cells.
   These organic forms physiologists denominate Elementary
Tissue.   When united, they form Primary Tissue.
   39.   Histology;   Proportion  of  Tissues  in  the  Body.—
Histology is the science of Tissues.   Tissue  forms nearly the
whole of the solid portions of the body.  By means of the  mi-
croscope, they have been examined  with great care, and  de-
scribed.
   40. Fluids  of the  System;  Hygrology.—Before entering
upon a  description of  the tissues, it seems desirable, at least,
to enumerate the different fluids found in the system, though a
  36. Define organic and inorganic structure.  87. Give the cause of organization.
S3. State the three simple forms of organized structure. What is Elementary Tissue ?
What is Primary Tissue ?  39 Define Histology.  What forms the solid parts of Urn
body ? 40. What Is Hygrology ? 
AND  PHYSIOLOGY.
15
fuller description of them will be  given further on.   These
fluids contain the  elements  of the tissues.   That  part of
anatomy which treats of them is called Hygrology.
   41. Lymph.—Lymph,  a  transparent, coagulable fluid,  in
the lymphatics, emptying into the blood.
   42. Chyle.—Chyle, a white, coagulable fluid, derived from
the food in the intestines, and conveyed to the blood.
   43. Blood.—Blood, in the veins  and  arteries, from which
nearly all  the parts of the system  are  sustained, a coagulable
fluid, with an alkaline reaction.
   44.  Scrum.—Serous secretions,  fluids found on  various
serous membranes,  as the pleura, peritonaeum,  pericardium,
and membranes of the brain and ear.
   45. Transudations.—Transudations, vapor from the lungs,
and  sometimes  from the skin; also, fluids in some of  the tis-
sues,  more especially  in certain  diseases,  as  dropsy in the
head,  chest, and abdomen,  certain  sweats  and  discharges in
cholera, etc.
   46.  Exudations.—Exudations,  "any  organizable  fluid
spontaneously separated  from  the blood vessels, without rupt-
ure of their walls," chiefly occurring  in inflammations,  and
wherever new  material is required  for repair of the system.
The  pus of wounds  and sores is an example of exudation.
   47. Mucus.—Mucus, a viscid mass capable of being drawn
into threads, secreted from the mucous membrane,  but differ-
ing in different parts.
   48. Gastric  Juice and  Pepsin.—Gastric  fluid,  a  fluid
secreted by the stomach, containing a substance called Pepsin.
which aids in digestion.  It contains a  little free chlorohydric
and lactic acids.
 41. What is Lymph and  what becomes of it?  42. Define Chyle and state what be-
comes of it.  43. Define the  blood. 44. What membranes secrete the serum ?  45. Defina
transudations.  In what diseases do they occur? 46. What are exudations?  When are
they serviceable? 47. What does the mucous membrane secrete?  48. Define and de-
icribe the secretions of the stomach. 
16
II I T C H COCK'S   A N A T O M Y
Fig. 4.
          Oo3 o o
„0bs'"c°  eAo
O ^rP 0°°
   49.  Intestinal  Fluid.—The  intestinal fluid,  a  colorless,
tenacious fluid, with strong alkaline reaction, whose  function
is to assist  in  digestion.   Secreted by the  epithelial cells of
the intestinal follicles.
                                        50.   Milk.—Milk,  a
                                     glandular  secretion,
                                     showing under  the mi-
                                     croscope   an   immense
                                     number of fat globules,
                                     suspended  in   a   clear
                                     fluid, as in fig. 4.
                                        51.   Saliva.—Saliva,
                                     a secretion chiefly from
                                     the parotid and  submax-
                                     illary   gland   into  the
                                     mouth, to assist  in diges-
                                     tion.
>o0^c/&^o0
                                        52.   Bile.—Bile,   a
                                     greenish   or   brownish
bitter fluid, secreted by the liver to assist in digestion.

  53.  Pancreatic  Juice.—Pancreatic fluid, a colorless, taste-
less, but somewhat alkaline fluid, secreted  by the pancreas to
aid  in digestion.
  54.  Urine.—Urine,  secreted by the kidneys.

  55.  Tears.—Lachrymal fluid for lubricating the eyeballs,
secreted by the lachrymal gland.

  56.  Oil and Wax.—Sebaceous secretions, fatty fluids thrown
out by what are called the sebaceous follicles of the skin, to
|:eep it moist.
  57.  Sweat.—Perspiration,  or  sweat,  a colorless,  watery
 49. What is the Intestinal fluid ? 50 How does milk appear under the microscope ?
*•.. What is the origin and use of saliva ? 52. State the secretion of the liver. 53. <fec,
Describe Pancreatic Juice.  Urine. Tears.  Oil and Wax.  57. Prom what glands ia
sweat produced ?
 
A.VU  PHYSIOLOGY.
n
fluid, with a saltish taste, and having odor, secreted from the
perspiratory glands.
                   Elementary Tissues.
  58.  Simple, or  Basement Membrane.—1. Simple  Mem-
brane.   This is  usually  a structureless  layer of coagulated
albumen, often not more than 20000th of an inch thick.   It
i>rms the walls of all cells, and is also spread out, as  an in-
ferior layer of the skin and mucous membrane,  and is then
called basement membrane.   It is the most  simple of all the
tissues,  yet it is the agent of secretion, and sometimes of ab-
sorption,  and these  Professor  Peaslee considers as its  vital
properties, though of a low grade.
  59.   imbibition.—Simple membrane also possesses the re-
markable property of allowing fluids to pass through it when
it is placed  between  two fluids ; the effect depending in part
upon the electro-chemical relations of the substances, but not,
as generally supposed, on the  difference of  specific gravity
of the liquids.   This is called endosmose and exosmose, or
Imbibition, and is the principal  means  by which fluids are
made to  pass from one part of the system to another, where
no distinct vessels are provided for that purpose.
  60.  Simple Fiber.—2.  Simple  Fiber.  This  consists es-
sentially of threads of coagulated
fibrine,  whose average diameter is
about o 3'o 0th of an inch thick.  It
does not appear to be a permanent
constituent of the body,  but only
a basis  for the development of the
more complicated tissues.  A good
example  of the simple fiber may
be seen in the  membrane lining
the inside of an  egg  shell,  as in
Fig- 5-    ____________________
 53. What is simple membrane ?  How thick?  Where is it found ? What other name
is given to it? 59. Describe Imbibition. What purpose  does it effect?  60. Describe
simple fiber. Its size.  Where best seen 1
 
18            HITCHCOCK'S  ANATOMY
   61.  Shape  of Cells.—3.  Cells.   These  are merely mem-
branous bags, or vesicles, from ,£-0th to eu'ooth of an inch in
diameter, filled  with some kind of  liquid, or solid substance
When  free,  the  form is spherical, or  spheroidal, as in Fig. 6.
But, as they press against one another, they are brought into
a polyhedral form, as in Fig. 7, showing a group of fat ve-
sicles.

              Fig. 6.                         Fia. 1.
   62.  Contents  of Cells;  Granules; Nucleus and Nucleo-
lus—The fluid of cells is transparent, except  in  the case of
blood.   In it there generally float an immense number of gra-
nules,  having no investing membrane, but sometimes they are
thus invested.  Each cell has also a nucleus and a nucleolus ;
the first being a globular, or lenticular body, from  e^Voth to
eo'ooth of an inch in diameter,  attached to, or imbedded in the
Wall of the cell, though  some  are  free.   The nucleolus  is a
granule within the nucleus.   Both are shown, as well as the
common granules, in Fig. 6.

   63.  Appendages of Cells.—Sometimes cells have  a sort <I
tail attached  to  them, and  are hence  called  caudate, as  in
Fig. 8.  Sometimes, too, they are stellate, as in Fig. 9, show-
ing the pigment cells of a frog's foot.
 61. Define cells. What is the original form of them ? How do they acquire the polv-
hedral form? 62. Explain nucleus, nucleolus and oell wall.  63. What are the annendacei
nf cells ?                                                    8
 
AND   PHYSIOLOGY.

           FlG  8.
1!)
Fig. 9.
   64. Cytogenesis.—The cell is the most important of the ele-
mentary tissues, for, by its  multiplication, most of  the othar
          64. Give the process by which cells increase and form tissues. 
20            HITCHCOCK'S  ANATOMY

tissues in animals and vegetables are made up.   This is called
cytogenesis.   The increase usually takes place by duplicative
subdivision, which is shown on Fig. 10.  The cell a a first
becomes elono-ated, as at b, and  then it  divides at c c.   The
subdivision going on will  give  an increase in lapid ratio—2,
4, 8, 16, 32, etc.  Fig. 11  shows an example of this division,
                                A,  B,  C,  D,  in  its earlier
             Fig. io.             stages, and  E,  F, G, H,  in.
              ec                its  more advanced condition.
                  Fio. 11.
A             B             C             D
granules into cells;  or they are even produced in the midst of
a formative fluid (called a blastema), poured out from the blood.
 Describe the mode of formation as illustrated in Figures 11 and 12.  What is the
Blastema? 
AND  PHYSIOLOGY.
21
  65.  It  is  in these
ways  that  most of the
tissues of the body are
built up, and the animal
enlarges  to its full size.
It has been maintained
that all the tissues orig-
inate  in cell  develop-
ment.    But,  in  some
cases,  simple fibers and
membranes  seem to be
formed directly out of
an  organizable  s u b -
stance, without the in-
tervention of cells.

  66.  Vital  Force  of
Cells;  Chemical Trans-
formations; Vitalization  of  the Cells; Change  of  Form;
Development of Nerve   Force.—The  multiplication  of cells
is one of the manifestations of the vital  force inherent in tbarn
Another is the chemical  transformations exerted upon the con-
tents  of the cell  in some instances, whereby  new products
are generated.   Another is  the vitalization of a  portion of
the cell contents,  whereby  they are  able  to  produce new
cells.   Another is permanent changes of form in connection
with  growth    Another is temporary changes of  form, ac-
companied with sensible motion, as in the  oscillatory move-
ments of the  leaves  of Hedysarum  gyrans,  and the  fold-
ing of the leaves of the Mimosas upon  touch.   Finally, tie
development of nerve force from cells, by which all  the bodily
operations  may be modified, and  which  is intimately connected
with mental agency.

   67. Periods in the Life of the  Cells.—In cell life there is a

  65. Show how the tissues of the  body are made up. 66. Mention the different changes
which cells  undergo.
 
22            HITCHCOCK'S  ANATOMY

period of augmentation,  another of perfection, another of de-
cline, and, finally, one of cessation.  So long as vitality can use
chemical and  physical agencies for building  up the  system,
they tend to its preservation, but, when life ceases, they tend
to its  destruction, not,  as is generally  thought, because the
vital principle has not the power of resisting these agencies,
but because it can no longer turn them into the channel for pre-
serving the system.
                 PRIMARY  TISSUES.
  The chief mass of the animal system is made  up  of the ele-
mentary forms that  have been  described,  variously combined
so as to form plexuses and webs,  which are called primary
tissues by some, and compound tissues by others.   They are
differently  classified  by different writers.   The arrangement
which follows is that of Professor W. B. Carpenter :
               1.  Simple Fibrous Tissues.
  68.  White and  Yellow Fibrous Tissues.—This embraces
the white and yellow fibrous tissues, as well as  the areolar or
connective  tissue of other writers.   The white fibers are  from
isVootb to the ao-oo-oth of an inch  in  diameter, and form the
tendons, ligaments, and fibrous membranes.  (Fig.  13.)   The
Fig 13
Fig. 14
 67. Give the four different periods in the life of cells  68. Give the size of the fibers
»f white and yellow fibrous tissues. 
AND  PHYSIOLOGY.
23
yellow fibers are about  ?s'6oth of an inch in diameter and form
a part of the larynx, and the middle coat of the arteries.

   69.  Areolar Tissue.—The areolar tissue consists of fibers
of white and yellow tissue interwoven, so as to leave irregular
spaces, or areolae, between them.   This tissue originates from
cells, as is shown in Fig. 16.   The areolar tissue is more widely
diffused than any  other in the body, so that  if it were possi-
ble to remove all but this one, the form of the part would be
preserved   It surrounds all the arteries and veins, the nerves,
muscles and internal organs; and it forms one of the layers of
the skin and mucous membrane
          2.  The Fibro-Cellular Membranes.

  70.  One of the layers of the skin, of the mucous membrane,
and the serous and synovial coat that lines the shut cavities of
the body, is composed of interwoven fibers of simple basement
membrane , and of one or more layers of cells  upon the free

 "^Twhat is the composition of areolar tissue?  What of its abundance In the body?
Where is it principally found ? 70. Describe the fibro-cellular membrane.
                            2
 
24
11 I T 0 H C OCR'S  .V \ A I' O M V
surface.   This is the fibro-cellular membrane or tissue.   Its
position and character will be. better understood when the parts
above referred to have been described in subsequent sections.
Fig. 17.                                 Fig. 18.
3.  Cellular Ttssues
   71. Fat  and  Cartilage—These embrace the adipose  tis-
sues, Fig.  17, and the cartilaginous. Fig  18.  The first is the
usual form of fat, wherever it occurs in the system.   It retains
the pure form of the primitive cells.  In  cartilage, also,  these
cells sometimes exist alone, but more frequently they are inter-
woven with fibers, as seen by the figures.

                   4.  Sclerous Tissues.
   72.  Bones  and  Teeth.—These constitute the bones  and
teeth, and are composed of an animal basis  of fibers and cells ce^
mented together  by phosphate and carbonate of lime.  Fig. 19,
which is a  transverse section  of one of the bones of the arm
will give an idea of the  arrangement of the animal matter
the earthy  part having been dissolved by acid.   Fig. 20 shows
a transverse section of the shoulder blade, exhibiting the dark
spaces called lacunae.
  Tl. Describe fat and  cartilage.  72. What is the comjKisition of the bones and tho
Ueth ?  73. What are the capillaries ami absorbents? Give the size of the capillaries. 
and  physiology.

         Fig.  19
25
                   5.  Tubular Tissues,
  73. Capillaries  and               kig 20
Absorbents.  —  These
form those minute blood
vessels called capillar ies.
and others called lym-
phatics or absorbent ves-
sels, which exist in every
pirt of the  body,  and
are  distinct  from,  al-
though  connected with,
the  arteries  and veins.
The  capillaries  con-
necting these are from
 2i-o0th  to   3T'oSth  of
 
HIT (.' .'I C O C K ' S  ANA T (') M Y
Fig. 21.   an iiitili ia diameter, less often than the blood cor-
         puscles.   In some other animals  they are  larger,
         as may bt 3een in the capillary plexus  of a frog's
         foot,  shown in Fig.. 9.   The lymphatics abound
         with valves, u.s may be seen in Fig. 21.
                   6. Muscular Tissue.
            74.  Striped and  Smooth  Muscle.—This tissue
         is made up of  tA\o forms of fiber, the striped and
         unstriped.   The stripes in  the first form run both
         transversely and  longitudinally,  as  may be seen
                              Fig. 22.
Fig. 23.
<1
in Fig. 22.  When separated longitudinally, the
fibriliac  have  a beaded appearance,  each  bead
being  in fact  a cell, as  is  here represented  in
Fig   23, which shews  the  celld  a  when  most
relaxed, and b when most contracted.   Muscular
fiber  is capable  also of  being divided crosswise
in the direction of  the transverse striae into discs,
as seen in  Fig.  24.    Both  the  striated (striped)
and   non-striated  muscles  originate in   cells.
Figs. 25 and 26 show their development.
   75.  Myotility.—The  grand  peculiarity  of
muscular tissue is its  power  of contraction—a
phenomenon as mysterious and  wonderful  as
any  thing in  nature.  This is  called myotility
or contractility.
 What do the lymphntics abound in?  74. Distinguish between the striped and the
unstriped muscular fiber. Give the reason of the difference between a and 6 iu Fig 23,
IS. Define myotility. 
AND  PHYSIOLOGY.
21
Fig 24.
Fig. 25.
Fig. 26.
   76.   The Chemical Composition  of  Muscle.—The chem-
ical  composition of the muscular tissue  is almost exactly the
same as that of blood, as  the following analysis will show  :
                                 Blood.         Muscle.
            Carbon................ 51.83         51.95
            Hydrogen.............  7.67          7.17
            Nitrogen.............. 15.01         15.07
            Oxygen...............21.36        - 21.39
            Ashes................  4.23          4.52

                                100.00        100.00
76. State the chemical composition of muscle. 
28           Hitchcock's   anatomy.

                   7.  Nervous Tissue.
  77. Nervous Tissue; Tubular Cells.—This, like some of
the other tissues, is composed of cells, fibers and tubes, but it is
distinguished from all others by its vital endowments.  In the
ordinary nerve trunks the tissue is the fibrous or tubular, as
is shown in fig. 27, A,  B, and C  In C some of the original
cells are shown.
                          Fig. 27.
or cells, as is________________------
shown in the ganglion of a mouse on fig. 28.
 77. How is nervous tissue to be diitinguished from all other tissues?  78. Describ«
the vesicular cells. 
                 AND  PHYSIOLOGY.              29

  Another primary element of the nervous system  is com-
posed of nucleated  cells, containing a finely granulated sub-
stance.   These sometimes have  processes which give them  a
caudate or stellate form, as in Fig.  29.

                           Fig. 29.
  79.  An Organ. The System.—Such are the tissues which,
combined  in various  proportions, make up the organs of the
human body.  And by the term organ we mean a part usually
composed of several tissues adapted to certain functions.  And
though harmoniously  united  into a single system,  that is, the
body, the anatomist can dissect and describe them separately.
In this work the following order will be adopted:
  1.  Osteology,  or an account of the Bones or framework of
the system.
  2. Myology, an account of the Muscles or the moving pow-
ers of the system.
  3.  Splanchnology, or the Nutritive Organs.
  4.  Angiology, an account of the Circulating System of the
arteries and veins.
,. What is the system ?  What is Osteology ?  Myology? 
30           HITCHCOCK'S  ANATOMY
  5. Pneumonology, or an account of the Respiratory, Vocal,
and Calorific Organs.
  6. Ichorology, or the Lymphatic and Secreting System.
  7. Neurology, or  the history of the Nervous System, the
vivifying power.
  8. The Inlets of the soul, or the Senses.
  9. Religious teachings of the subject. 
             CHAPTER   FIRST.

THE FRAMEWORK OF  THE SYSTEM.—OSTEOLOGY, OR
           A DESCRIPTION OF  THE BONES.
         DEFINITIONS   AND  DESCRIPTIONS.

   80. Chemical Composition  of  Bone.—The  Bones  of all
vertebrate animals are principally composed of the Phosphate
and Carbonate of Lime, and, with the exception of the Teeth
and articular extremities,  are closely covered by a firm mem-
brane called the Periosteum.   By chemical analysis the com-
position is as follows :

           Organic substance (Osteine or Cartilage)  33.00
           Phosphate of Lime...................  57.00
           Carbonate of Lime....,...............   8.00
           Fluorid of Calcium...................   1.00
           Phosphate of Magnesia...............   1.00
                                            100.06

   81. Cartilage and Salts of Lime  shown.—Hence we  see
that the principal constituents of bone are  the salts of Lime
and Cartilage.  The former can be easily obtained by burning
the bone a while in  a hot fire, which appears  like a white
powder when crushed.    The  Cartilage  is  obtained by  im-
mersing it for a considerable time in a dilute acid, when we
have the form of the bone perfectly retained, although nothing
is  left but cartilage.   Its  elastic  character may be inferred

 80. What are the principal ingredients of bones?  Where is the Periosteum found?
Give the chemical analysis.  81. How can the earthy ingredients be shown?  The car-
Wage?                       j0» 
32            HITCHCOCK'S   ANATOMY

           Ftg. 30.            from Fi<r. 30, which is a human
                             Fibula tied in  a knot after hav-
                             ing  been   immersed for  some
                 f|w^     time in muriatic acid.
                   SlS|        82.   Mechanical   Construc-
                  jHr      tion of  Bones.—As  a  general
                             law  the  extremities  are  the
                             largest, and the bodies or shaft"
              ll!|l§il|j        are  smooth and of a  uniform
                             surface.     They are  in  most
                             cases so  constructed as to give
              ^ifii«j|ggj|||    the  greatest strength and sup-
                             port, and at the same time fur-
                             nish as little weight as possible.
                             Hence the long bones are most-
                             ly hollow,  or have an  arched
                             form,  while the flat bones are
portions of a circle or sphere.   In the face also the bones are
not all solid, but some of them contain large cavities, so that
firm attachment may be given  to  the muscles, and protection
to the m >re delicate parts.
   83. Average Weight of adult  Skeleton.—The weight  of
the skeleton  is as 10.5 : 100,  or about one  tenth the weight
of the whole  body.  And since the average weight of an adult
man is 136  pounds, the weight of an  adult skeleton  is about
13.5  pounds.
   84. Strength  of  Bones.—The  power  of  the  human bones
as levers when compared with  different substances is  remark-
able,  as  is seen by the following table.
           Freestone (sandstone)..................  1.
           Lead  ...............................  6.5
           Elm and Ash (wood)...................  8.5
           Box, Yew, and Oak.................... 11,
           Human Bone......................... 22.
  82. Which part of the bones Is generally the  largest?  Why are many of the bonet
hollow or partially so?  83. Give the weight of the human skeleton.   What is its pro-
vortion to that of the whole body? 84. Give tho comparative strength of the bon«s. 
AND  PHYSIOLOGY.
S3
That is,  bone when used as a lever is  22 times  as strong as
Sandstone,  3^ times as strong  as Lead,  nearly 2f times as
strong as Elm and Ash, and 2 times as strong as  Box, Yew,
and  Oak timber.

   85. Microscopic Structure of  Bone.         FlG-  31-
Haversian  Canals. — Examined  by
the microscope the bones  are found to
be made up  of plates or  layers for
the most part, arranged concentrically
in the  long  bones, and  in  parallel
layers in  the  flat  ones.    These are
traversed in  all (.".irections, avA  espe-
cially in   their  long  diameters,  by
minute  tubes  or vessels called Ha-
versian  canals, which are  also  en-
circled  by several  laminae or  plates
besides  those  following  the  general
outline of the bone.  Fig. 31.   These
canals have a diameter varying from
__.i_._-  to oi-otb of an  inch,  while the
accompanying  lamellae show a  thick-
       1   J  °           .         rp,     magnified 15 diameters. 1, <
neSS Of eo'eTrth Of  an  inch.     Ifiey  layer. 2 and 3, inner layers
sometimes  contain  a capillary  vessel,
but more usually carry only the nutritive and  watery portion
 of the blood.
   8G. Lacuna,  Canaliculi.— Besides these canals we  find _
 smaller set of vessels  or cells located directly in the substance
 of the concentric lamellae, called Lacunae or Bone Corpuscles,
 which average ToVoth of an inch in length, and carry the fluid
 which nourishes the bone.   These are of a black appearance,
 of  an oval form, and with rays divergent  in all directions, as
 Transverse  section of  bone
magnified 15 diameters. 1, Outer
 85 now pre the particles of matter arranged in the long bones ?  How in the flat
ones' Describe the Haversian canals. Their diameter.  What vessel does each one
contain and what is the purpose of that vessel?  86. What are the Lacunas or Bon.
Corpuscles J 
34
HITCHCOCK'S  ANATOMY
Fig. 32.
Lacunae of Bone, a, central portion.
    b, canaliculi or Bone Pores.
seen  in  Fig. 32.   These
rays  are  minute  canals,
and  nearly  all  of  them
anastomose, or have com-
munication with each other.
They are called Canaliculi,
or Bone Pores, and mea-
sure  3oiooth of  an  inch
in diameter.
Fig. 33
W
:W<._
*_..«
   87.   Ultimate  Granules.—The ultimate histological ele-
             ment,  or the smallest element of bones as yet
             discovered, is made  up of pale  oval granules,
             about  foVoth of an inch  in diameter.   These
             granules constitute all the substance of the bone
             except the minute vessels already mentioned.
   88.  Hence the microscopic elements of bone are four :
   1. Haversian Canals.
   2. Lacunae or Bone Corpuscles.
   3. Canaliculi or Bone Pores.
   4. Ultimate Granules.
   89.  Periosteum.—In all parts of the  body, both solid and
fluid,  we find that  nature has made  ample protection  by
providing for nearly every organ a firm  membranous sheath.
This not only serves as  a  protection  and  support,  but  in
many  cases  a means  of  nutriment.   Upon  the  bones ac-
cordingly  we  find  a  very firm whitish  yellow  membrane
closely attached  to  them  in  most places, and  very  smooth,
called  the Periosteum.  This occurs on every part of every
bone, except at the articulations, and upon the crowns of the
teeth.   It is,  when healthy, perfectly insensible, and contains
the vessels  which ramify  into  the  bones, being  in fact the
 What.are the Bone Pores or Canaliculi ?  87. What is the smallest or ultimate element
of bones ?  88. Give the four microscopic elements of bone.  89. What is the color of
the Periosteum ?   On what part of the bones is it wanting?  What  two important
purposes does it subserve ? 
AND  PHYSIOLOGY.
35
nutrient membrane of  the bones.   Besides
this  function,  the  periosteum  serves as  a
point of  attachment  for  the ligaments  and
tendons, in as much  as they could not  find
firm attachments  on the bone itself.
  Remark.—Diseases  of  Periosteum.—In
the diseases known as Felon  and Fever Sore,
the Periosteum is the seat of the inflamma-
tion, although, if  it be  not soon checked, the
bone itself becomes implicated.
  90.  Processes  of Bones.—The  bones  of
animals  are  not constructed after any regu-
lar  geometrical form  or curve, but are mod-
eled upon  the plan  which  may  secure  the
          p           1__**1°    _*      ■    x Vl luateuin ux ii 11 u li ic-
greatest  firmness  and   tacility  ot  motion. ,.U8 partly taken off.
Accordingly  we  find  their  surfaces  quite
uneven,  presenting in  many places  prominent  projections,
which  serve  as a firm  point of attachment for muscles and
ligaments.   These are  called Processes,  and  are  generally
found  near the extremities of bones,  and are  largest where
the greatest  strength of muscle  and ligament is required,  as
shown in the bones of the lower extremities.

  91.  Nutritious Foramina.—Upon  nearly all the bones  of
the body may be found  small tubular openings which, after
extending for a short distance into the bone, ramify and give
off the minute capillary vessels which  circulate through  the
larger Haversian canals.   They  are  called nutritious fora-
mina, or openings, since they convey nutriment to a largo
portion of the bone.
   92.  Four  Classes of Bones.—Bones are divided  according
to their shape into four classes : long, flat, short, and  irregu-

  What is the seat of Felon and Fever Sore? 90. What is the general outline of bones?
What are Processes?  91. What are the nutritious foramina, and with what  vessels do
they communicate ? Their use ?  92. Give the four classes of bones, and give examples
of the long ones.
Fig. 34.
 
36            HITCHCOCK'S  ANATOMY       4

lar.   The long ones are mostly found in the extremities, and
consist of a hollow shaft with enlarged and partially smoothed
extremities,  and sometimes a rough or elevated  portion along
their central portions.   Those which belong  to this class,  are
the Clavicle, Humerus,  Radius, Ulna,  Femur,  Tibia,  Meta-
tarsus, and Metacarpus, Phalanges and  Ribs.
   93.  Short Bones.—The ShoY. hones are irregularly cuboid
in form, and are found in those places  where there  is  but
little motion  of the  part.  They  are the Vertebrae, Coccyx,
Carpus and  Tarsus,  Patella,  and Sesamoid bones.
   94.  Flat  Bones.—The Flat bones are arranged  to enclose
and protect  cavities.   Those  of the head  are  made of two
layers  of bony matter, with  an intervening  porous  substance
called the Diploe. These are the  Occipital,  Parietal, Frontal,
Nasal, Lachrymal,  Vomer, Sternum,  Scapula, and the  Os
Innominatum.
   95.  Irregular Bones.—The Irregular  bones  are  those
which belong to  neither of  the preceding  classes, and have
no typical  form.  They are the Temporal, Sphenoid,  Eth-
moid, Superior and  Inferior Maxillary,  Palate, Turbinated,
Hyoid, and  Sacrum.
   96.  Development   of  Bone  from  Cartilage.—The  early
condition of bone is  that of  cartilage, which has the general
outline  of the  bone, and  from the  subsequent process may
be called the mould of the  bone.   Very early in  life, and
even before birth, bony matter begins to  be deposited in  tho
cells of the  matrix   (cartilage)  until  at length,   the  whole
becomes solid, as it  is found in adults.   At birth the only
bone which is completely ossified is that portion of the tem-
poral  called  the  petrous, which contains  the organ  of hear-
ing,  while  all  the  bones  are  not  completely  ossified  be-
fore the 12th year of life.    This process of hardening, or os-
 93. What is the general outline of short bones and where are they found ? Give ex-
amples.  94. Give the use of tho  flat bones.  Examples also. 95. What aro some of
the irregular bones?  90. What is the first stage of bone?  When is the process of ossifi-
cation complete?  What bones are the first that become ossified? 
AND  PHYSIOLOGY
37
sification,  begins at
certain points,   and
continues  until  the
whole  is completed
as  is  seen in  the
Fig. 36. In some of
these  bones there is
but   one  of  these
centers, or points,
where  ossification
commences, while in
the  Sphenoid  there
are 12.
   97.  Number of
Bones.—The  num-
ber of bones in  the
human  system  is
reckoned differently
by different anatom-
ists  since  many of
the  bones  are  well
exhibited  only  in
hard    working   or
well developed mus-
cular subjects.  The
number 216 will  be
given  in this book
as taken from Eras-
mus Wilson,  whose
work on Anatomy is
adopted as the  text
Fig. 35.
: -.	«» .. «a_>*-:"	
*>	*& ■•<__. ■•;«	
	e_$_"°«	__>
«©> <E&, <tj.«_		
	■■*a_B.~	
		
*B>	egCb	<a_P
as*	•■■■■/_»	<S_j, ■
  Section of cartilage near the point of ossification.
1, ordinary appearance of cartilage.  2 and 3, more a<!»
vanced stages of ossification.  1', 2' and 8' portion?
1, 2 and 3 more highly magnified.
book in nearly all the medical schools of this country. This in-
cludes the teeth, and sesamoid bones, of which the latter are not
constant in every individual.  They are summed up as follows:

  97. What is the number of bones in the human body ? Give the different groups. 
38
HITCHCOCK'S   ANATOMY
FlG. 36.
Fig. 37.
&
  A knee joint showing points of ossification,
               1, 2 and 3.

  Head..........................   3
  Ear............................   6
  Face..........................  14
  Teeth.........................  32
  Vertebrae, Sacrum and Coccyx....  26
  Os Hyoides,  Sternum and Ribs....  26
  Upper Extremities...............  64
  Lower Extremities..............  62
  Sesamoid Bones.................   8

                                    246.

   98.  Vertebra;,  Groups of Verte-
brae, Cervical Vertebrae.—The Ver-
tebrae or  Spinal Column  claim the
first  attention,   since  they   are the
  Description of Fig "7. Lateral view of the Spinal
Column. 1, Alias. 2, Axis (second Vertebra.) 3, Last
Cervical Vertebra.  4, Last Dorsal Vertebra.  5, Last
Lumbar.  6 and 7 Sacrum.  8, Coccyx. 9, a Spinous
Process  10.  Intervertebral Foramina. 
AND   PHYSIOLOGY.
39
Frontal Bone.  FiG.  38.   Parietal Bone.
Temporal Bon*
Clavicle.
Ilium.
Patella.
Tarsus.
Metatarsus.
Phalanges. 
40
HITCHCOCK'S  ANATOMY
first developed bones,  and the center around which the others
are formed.   They may be separated into the true and false :
or those which are  separable from,  and movable  upon each
other, and those which are  firmly joined  together.   Of  the
true vertebrae there are three  sections, named  in  accordance
with their location on the  body :  Cervical, Dorsal,  and Lum-
bar. The Cervical,  or  those  of the neck, are seven  in number
the first and second of which are the most remarkable.  T. 8
first is named Atlas, from the mythological  story that  a giant
of this name supported the earth on his shoulders, and it ia
Fig. 39.
Fig. 40.
 The Atlas.  1, Anterior Tubercle.  2, Articular
Face. 3, Posterior surface of Spinal Canal. 4, In-
tervertebral Notch.  5, Transverse process. 6, Fo-
ramen for Artery.  7, Superior oblique process.
8, Tubercle for transverse Ligament.
  The Axis. 1, Body. 2, Proces-
sus dentatus. 3, Articulating sur-
face.  4, Foramen for vertebra']
Artery. 5, Spinous process.  6 and
7, Oblique processes.
upon this one that the head is moved in a direction backwards
and forwards.   The second, called Axis, is characterized by
a projection or  pivot,  which  admits  motion  of the  head in
a horizontal direction, but  in  no other.  It is the dislocation
of this process, and the consequent pressure  upon the spinal
cord that causes death in criminals executed by hanging.

  99. Dorsal Vertebra;.—The Dorsal Vertebrae, or those of
the back, are twelve in number, and give attachments to all
the ribs.   The central portion or body of each increases  frottt
above downwards, that they  may more firmly support the
superincumbent weight of the body.

 98. Why are the Vertebra first described ?  What two groups may they be divided
into?  What other three sections of Vertebras?  What is the name of the first and
second  Vertebra? 97. How many Dorsal vertebrae, and what bones are attached to
<fccm ? 
AND  PHYSIOLOGY.
41
Fig. 42.
  A Dorsal Vertebra. 1, The Body. 2 and
T, Faces for head and tubercle of Rib. 8,
Upper face of the body. 4 and 5, Interver-
tebral Notch.  6. Spinous process.  8 and
9, Oblique processes.
 The Sacrum. 1 and 2, Articular sur-
faces. 3, Promontory of the Sacrum. 4
and 10, Lines of former division of Sa-
crum. 5 and 6, Foramina. 7, Sacro Ischia-
tic Notch. 8, Aire of the Sacrum. 9, Ob-
lique processes.
   100. Lumbar Vertebra;.—The vertebrae of the  Loins, or
the Lumbar, are five in number,  and are the largest members
of the spinal column, since  they are the only bones in  this
part of the body.    They are  more massive and  solid  in all
their parts  than the rest  of this column, that they may be
equal to the strength required of them.
   101.  Sacrum.—The Sacrum is a  single  bone,  although
its typical form  is  that  of five  vertebrae, which  are actually
found in some animals.  Its appearance is that of five verte-
bra, which are partially anchylosed or grown together.    The
form of the  bone  is somewhat like a  wedge, with  the base
directed upwards,  and the  point curving inwards and  for-
wards.
   102.  Coccyx.—The Coccyx is the lower
extremity of  the  Spinal  Column, formed
of  four anchylosed  and imperfect  verte-
brae ; and it is an extension of these bones
in the monkey which makes the tail.      ^ j^'^S
                      Sacrum. 4 and 5, Notches to form Foramen.  6, Last bone.
FIG. 43.
 100 How many Lumbar Vertebra? Why are they the largest in size ? 101. Describe the
Sacrum. H.w many rudimentary vertebra does it consist of? 102. Describe the Coccyx. 
42
HITCHCOCK'S  ANATOMY
  103.   General  Remarks on  the  Spinal  Column — The
Spinal Column viewed as  a whole  may  be considered  as
made up of four cones, owing to the different  sizes of the ver-
tebrae.  The apex of the upper one commences with the Atlas
and  extends as far as  the first  dorsal vertebra.   Here the
second one commences in an inverted  position, extending over
the upper three dorsal vertebrae.   The third  reaches Avith  its
Lase  as  far  as the top  of the  Sacrum, where the inverted
fourth one terminates with the Coccyx.    Viewed from the
front the spinal column should be in a straight line when in a
healthy condition;  but a lateral view shows two  curves, one
at the lower part  of the neck, and the other at  the lumbar
vertebrae,  the  design of this curvature being to place the
head and  its delicate contents upon an elastic and flexible
support, and the design of  the straight position  in the other
direction, being to  give equal tension to the muscles on both
sides.
   104. Intervertebral  Cartilage.—Between all the vertebrae
is placed a thick cushion of cartilage.  This  by yielding not
only allows a free and ready motion to the column as a whole,
but  is an  additional protection to  the  brain, by  diminishing
the severity of any vibration communicated from  below.

   105.  Bones of  the Head.—The  Skull  may  be  considered
as the superior expansion of the spinal column, when it—the
spinal column—is  taken as the center of development of the
whole body, which contains in the cranium the  brain,  and in
the face most of the organs of sense.

   106.  In the Cranium or true skull are eight bones:
          1 Frontal,        2 Temporal, '     2 Parietal,
          1 Occipital,      1 Sphenoid,       1 Ethmoid.

  103. Of how many cones may the Spinal Column be considered as composed? From
what direction does the Spinal Column appear in a straight line? What curvatures doef
a lateral view show? 104. What substance do we find between the vertebra? Give
Its use. 105. What may the Skull be considered as?  What organs does it contains
106. Give the bones of the Skull. 
AND  PHYSIOLOGY.
43
   107.  Frontal,
Temporal,   Parie-
tn(,   Occipital,
Spdcnoid, and Eth-
moid   Bones.—The
Frontal Bone is sit-
uated  in  the  upper
and  front part  of
the head, occupy-
ing that  portion of
the skull called the
forehead.    It  is
mainly a flat bone,
but the  portion
lying above the eye
is hollow, in order
that protection may
be afforded  to  this
delicate  organ,  as
well as to give sufficient
prominence  to the  up-
per  part of  the  face.
The two Temporal Bones
cover  the front part  of
each  side of  the skull
in that  position com-
monly  known  as  the
temples,  and  each bone
is a  little  larger  than
the space which  is pro-
 tected  by  the external
 ear.   In the inner por-
 tions,  called the petrous,
 are  located  the  organs
Fig. 44.
 1, Frontal. 2, Parietal.  3, Occipital.
5, Nasal.  6, Malar.  7, Upper Jaw.
9, Mandible.

                    Fig. 45.
 4, Temporal
!, Lachrymal
  Frontal Bone. 1, Frontal Piotuberanco of righj
side.  2, Superciliary ridge.  3, Superorbitary
ridge, 4 and 5, Angular processes.
 107. What kind of a bone is the Frontal? Why is a portion of it hollow ?  Where are
the Temporal Bones located ?
I 
44
HITCHCOCK'S  ANATOMY
  Left Temporal Bone.  1, Squamous portion.
!, Mastoid portion. 3, Petrous portion. 4, Zygo-
matic portion.  5, Articulating surface for lower
jaw.  6, Temporal ridge.  7, Glenoid fissure. 8,
Mastoid foramen. 9, Canal  for  ear. 10, Groove
for digastric mi'sclc. 11, Styloid  process. 12, Va-
ginal process. 13, Glenoid Foramen. 14, Groove
for Eustachian tube.

              FiG. 47.
                Fig-46.                  0f hearing.    Directly
                                         behind the  external ear
                                         is felt a hard projection
                                         w iich  is  the   mastoid
                                         process  of   this  bone,
                                         and  serves  for  the
                                         attachment   of  many
                                         muscles,   which  move
                                         the head.  And directly
                                         in  front  of  the  ear  is
                                         another prominent pro-
                                         cess,  called  the  zygo-
                                         matic, which articulates
                                         with  the  malar   bone,
                                         and  to   which  is  at-
                                         tached one  of  the  ele-
                                         vator  muscles   of  the
                                         jaw.   The  two  Parie-
                                         tal  Bones are eminently
                                         flat bones of a  square
                                         shape, forming  the  es-
                                         sential parts of the pro-
                                         jections  on   the  back
                                         sides  of the head,  and
                                         uniting with each other
                                         on the median line,  up-
                                         on the top of the skull.
                                         They  join   with   the
                                         frontal bone in front, the
                                         temporal  bones  below
                                         and the  occipital bone
                                         behind.   The  Occipital
Bone  has  an  imperfectly  circular outline, and at its  lower
  What  is the mastoid process?  Where i9 the zygomatic process?  Give the form o
the Parietals.  What is the outline of the Occipital Bone ?  What is the large orifice ii
its lower part for?  Give the position and general outline of the Sphenoid Bone.  Witl
what bones does this articulate ?
  Left Parietal Bone. 1, 2, 3, 4, Superior, Infe-
rior, Anterior, and Posterior surfaces.  5, Ridge
for Temporal Fascia. 6, Parietal Foramen. 7 and
8. Inferior angles. 
AND   PHYSIOLOGY.
43
edge a large  orifice  for the
passage  of the spinal  mar-
row,  just  as it  enters  the
vertebrae.   It  is   in  the
most  posterior part of  the
skull,   joining   with   the
sphenoid in front, and rest-
ing upon the Atlas  verte-
bra.    The  Sphenoid  Bone
is  directly  underneath  the
skull,  extending from  side
to  side,   forming  a   very
small  portion  of the out-
side  of   the  skull  at  the
point   where  the  frontal
and temporal  bones  come
the  nearest to  each other.
From  its  name  we  learn
tHat it is somewhat  wedge-
e'^VMHf
  External surface of Occipital Bone.  1 and 4,
Semicircular Ridges.  2,  Occipital  Protube-
rance.  3, Attachment of ligamentum nuclie.
5, Foramen for Medulla oblongata. 6, Condyla
of right side.   7 and 8,  Condyloid Foramina.
9, Jusrular Eminence.  10, Jugular Foramen.
11, Basilar process.  12, Points of attachment
for odontoid ligaments.  13, Edge for attach-
ment with Parietal bone.  14, Point of attach-
ment for Temporal bone.
FIG. 49.
  The Anterior and Inferior Surface of the Sphenoid  Bone.  1, 1, Apophyses of Ingras-
sias.  2, 2, The  great Wings.   3, Ethmoidal Spine.   4, Azygos Process.  5, Sphenoidal
Cells, after  the removal of the Pyramids of Wistar.  6, Posterior Clinoid Processes.
7, Sphenoidal Fissure.  8, Foramen Rotundum.  9, Depression for the Middle Lobes of
the Cerebrum.  10, Surface for the Temporal  Muscle. 11, Styloid  Process.  12, Exter-
nal Pterygoid Process.  13, Internal Pterygoid Process. 14, Pterygoid Foramon.  15, Ar-
ticular Face for th» Os Frontis.  16, Points to the Sella Turcica. 
46
HITCHCOCK'S  A X A T O M V
shaped  in its  general  outline,  although  it  is  covered  and
filled with  cavities and  processes  for  the  protection  and
proper direction of  many of the  delicate  organs  which  pass
through it to their destination.   This  bone  articulates  with
all those  in the cranium, and  five of those in  the face, and
serves as a point  of attachment  for  twelve pairs  of muscles,
and  is one of  the  most complicated bones  belonging  to the
human  skeleton.
  The  last  bone  of  the  skull is  situated  at  the base  of
Cribriform Plate.  5, Superior Meatus.     A View of the Outside of the Vault ot
6, Superior Turbinated Bone.  7, Middle    the Cranium, showing the Sutures. 1, The
^v.rbinatedBonc. S, Os PI nun. 9, Sur-    Coronal Suture.  2, The Sagittal Suture.
face for the Olfactory Nerve.              3, The Lambdoidal Suture.
the front  portion  of  the cranium, between  the sockets  of
the eyes,  and behind the root  of the nose.   It is called the
Ethmoid  Bone.   Its outline is that of a cube, consistino- of a
perpendicular plate, and  two  lateral  portions.    From tho
fact that  it is extremely fragile,  owing  to  the great  number
of perforations which it contains, it derives its name from the
Greek word signifying a sieve.   It is so deeply seated that it
receives the attachments of no muscles.
   108. Sutures.—The  bones  of the  skull  are  united  by
Give the shape and position of the Ethmoid bone.
Why called Ethmoid? 
AND  PHYSIOLOGY.
47
Fig. 52.
ragged edges  called Sutures.   These are  small and rough
projections of bone  which  are  largest  at their extremities.
They are made to fit into the edges of tho opposite bone with
great firmness, thus joining the bones together, by essentially
the same process which in cabinet work  is known as dovetail-
ing.   The  name Suture  is  applied, since  when these  edges
are  perfectly  joined by this articulation, they resemble the
seam made  by  sewing together  two pieces  of cloth by the
"over and over" stitch.    Situated directly within these sut-
ures  are   frequently  found
small  bones, uncertain a-> to
number, sometimes two inches
in diameter, called Ossa Tri-
quetra.   No special use for
them has  been discovered as
yet.
   109.  The  Lower Surface
of the Skull.—The whole of
the lower surface of the skull
is extremely uneven for the
attachment of a  great number
of muscles, and the protection
of delicate nerves and  blood-
vessels  which  pass  to
from the brain and face.
and
   110. Bones in the Face.—
The Face is that portion  of
the head situated below a line
drawn  from  the orbit of the
eye to the passage of  the in-
ternal ear.  Its framework con-
tains fourteen bones. 2 Nasal;
  A Front View of che Skull, showing the
Bones composing the Face.  1, Os Frontis.
2, Nasal Tuberosity. 3, Supra-Orbital Ridge.
4, Optic Foramen. 5, Sphenoidal Fissure.
6, Spheno-Maxillary Fissure.  7, Lachrymal
Fossa, and commencement of the Nasal Duct.
8, Opening of the Anterior Nares, and the
Vomer.  9, Infra-OrbiUil Foramen.  10, Ma-
lar Bone.  11, Symphysis of the Lower Jaw.
12, Anterior Mental Foramen.  13, Ramus of
the lower Jawbone.  14, Parietal Bone. 15,
Coronal Suture.  IC, Temporal Bone. 17,
Squamous Suture.  18, Great  Wing of tho
Sphenoid.  19, Commencement of the Tem-
poral Ridge.  20, Zygomatic Process. 21, Mas-
toid  Process.
 How do the bones of the skull join with each other ? What process in cabinet making
does it correspond to?  What are often found in these sutures?  109.  What is the sur-
t»«o of the lower part of the skull ? 110. Give the boundaries of the face.
                              3 
48
HITCHCOCK'S  A N A T O M  V
2  Malar;  2  Lachrymal;  2  Superior Maxillary;  2  Palate;
2 Turbinated;  1 Inferior Maxillary;  1 Vomer.

   111. Nasal Bones.—The Nasal Bones are oblong, foursided
bones,  about an inch  in  length,  which together  form the
bridge  or base of the nose.
i                i
  An Anterior and Posterior View of the
Nasal Bones. Right Hand Figure. 1, An-
terior Inferior Extremity. 2, Articulating
Surface for its Fellow.  3, Surface for the
Nasal Process of the  Superior Maxillary
Bone. 4, Points to the Groove on the In-
ner Side, for the Nasal Nerve.  5, Articu-
lar Face for the Os Frontis.  6, Foramen
for the  Nutritious Artery.—Left Hand
Figure.  1, Posterior Inferior Extremity.
2, Surface for its Fellow.  3, Surface for
the Superior  Maxilla.  4, Groove for the
Internal Nasal Nerve.  5, Surface for the
Is Frontis.  6, Lower portion of  the
Groove for the Nasal Nerve.


   112.  Malar  Bones—The  Malar  Bones  give  the  promi-

nence  and form to the cheek.   They are  partially hollow, of

an irregularly quadrangular outline, and  articulate with  the

frontal above, the zygomatic process of  the temporal  behind,

and the superior  maxillary below.   The name  is from  the,

Latin  Mala, a  " cheek," hence cheek bones.

   113.  Lachrymal  Bones.—The  Lachrymal  Bones  are  the
Fig. 54.
  An Anterior View of the Malar Bone
of the Right Side.  1, Anterior Orcital
Angle. 2, Orbital Face.  3, Superior An-
gle for articulating with the Os Frontis.
4, External An le for the Zygoma of tho
Temporal Bone.  5 and  6, Inferior An-
gle and Surface for the Superior Maxilla
7, Nutritious  Foramen.
  How many bones in the Face, and what are their names?  111.  Describe the  Nasal
Bones. 112. What bones are found in the cheeks ? 
AND   PHYSIOLOGY.
49
smallest bones in  the  Face,  being  about fth of  an  inch  in
diameter.   They are situated  at the  inner angle  of the  eye,
and are named from the Latin  Lachryma, a " tear." since
the  tears  pass  into  the  nostrils through  a  canal  in  these
bones.   This bone is also called  Os Unguis.
                                               Fir,. 56.
          Fig. 55.
  An Anterior View of the Os Un-
guis of the Left Side.  1, Its An-
terior Inferior Angle.  2,  Orbitar
Plate and Side for the Os  Pla-
num.  3, Fossa for the Lachry-
mal Sac.  4, Superior Extremity.
                                A Posterior and Half Lateral View of the Pal-
                              ate Bone   1, Palate Pla'.e on its Nasal Surface.
                              2, Nasal Plate.  3, Pterygoid Process.  4, Sur-
                              face for Articulating  with its fellow.  5, Half
                              of the Crescentic Edge and Spine for the Azygos
                              Uvulae Muscle. 6, Ridge for the Inferior Spongy
                              Bone. 7, Spheno-Palatine Foramen.   8, Orbital
           Plate.  9, Pterygoid Apophysis. 10, Depression for the External Pterygoid
           Process of the Sphenoid Bone. 11, Same for the Internal Pterygoid Process.

   114.  Palate Bones.—The Palate  Bones are the  most ir-
regular bones of the  face, and  when  viewed in one  direction
resemble the  capital letter L.   They form  a part of  the orbit
of  the  eye,  the  wall  of the
nose,  and  a large part of the
roof  of  the  mouth  which  is
known as  the hard palate.
   115.   Turbinal  Bones.—
The  Turbinal Bones  (really
the   Inferior   Turbinated
Bones,   since   corresponding
plates upon the ethmoid bone
are called  Superior Turbinated
Fig. 57.
  An External View  of the Inferior
Spongy Bone of the Right Side.  1, An-
terior  Extremity,  for  resting on  the
Ridge of the Upper Maxilla.  2, Posterior
for resting on  the Ridge of the  Palate
Bone.  3, Hooked portion, for resting on
the Lower Margin of the Antrum Iligh-
morianum.  4,  Its Inferior Border.
  113. What are the smallest bones of the face, and why called Lachrymal ?  114. What
are the most irrecmlarly-shaped bones in the face, and what portion of the mouih Is
made up by the Palate Bones?  115. Give the description of the Turbinal Bonan, 
5)
HITCHCOCK'S   A X AT O M Y
Bones) are  curved laminae or thin plates of bone, resembling
a loose scroll,  and are  found  in each  nostril, for the purpose
of affording as large a  surface  as possible  for  the  expansion
of the mucous  membrane  of the  nose, which contains  the
nerves of smell.    The  name  Turbinal  or  Turbinated  is  ap-
plied because of their scroll-like appearance.
   116.  Superior  Maxillary Bone.—The  Superior  Maxilla-
ries  are the largest bones of the face, joining with each other
             Fir,. 58.                          Fig. 59.
  An External View of the Superior Max-
illa of the Left Side.  1, Orbitar Process.
2, Infra-Orbitar Canal.  3, Space for tho
Os Unguis.  4, Upper  part of the Lachry-
mal Canal.   5, Nasal Process, and Sur-
face for Articulating with the  Os Frontis.
6, Surface for the Nasal Bone.   7, Anterior
portion of the Floor of the Nostril. 8, Sur-
face for Articulating with its Fellow. 9, Al-
veolar  Process. 10, Points to the Depression
just below the Infra-Orbitar Foramen. 11,
Surface for the Malar Bone.
                                      The Inferior Maxillary Bone. 1, The
                                    Body.  2, The Ramus. 3, The Symphy-
                                    sis.  4, Alveolar Process.  5,  Anterisr
                                    Mental  Foramen.   6,  The Base.   7,
                                    Groove for the  Facial Artery.  8, The
                                    Angle. 9, Extremity of the Ridge for
                                    the  Mylo-Hyoid Muscle.  10, Coronoid
                                    Process.  11, Condyle.  12, Neck of tho
                                    Condyloid Process.   13, Posterior Men-
                                    tal Foramen.  14, Groove for the Infe-
                                    rior Maxillary Nerve. 15, Molar Teeth.
                                    1G, r.icuspidate Teeth.  17, 18, Middle
                                    and Lateral Incisors.

on the  median line, and thus form  a  portion  of the roof  of

the mouth.   Each one of them articulates  with ei-i-ht teeth,

with  all the bones of  the face but  the lower  jaw, and two  Cl

the  cranium.   Their  name  is  from the  Latin, Maxilla,  a

"jaw," and both of them constitute  the  upper jaw.

   117.  Mandible.—The  Inferior  Maxillary, or lower jaw  is
 116. How are the Superior Maxillarics situated?
of them ? 117. Describe the Mandible.
How many teeth are found in each 
AND  PHYSIOLOGY.
51
the only movable bone of the head or face.   It contains  the
sixteen  lower teeth, is of an arched  form,  and at each  ex-
tremity has a square-shaped process  for articulation with the
temporal bones,  and the attachment of muscles.
  118.  Vomer.—The
name of the Vomer is
derived from the  Latin
meaning  a  "plow-
share," on account of
its approximate resem-
blance  to that object.
It completely separates
the  nostrils  from each
other, and like the tur-
binated bones gives at-
tachment  to no  mus-
cles.
Fig. 60.
 The Vomer. 1, 2, Posterior and Superior Surface
hollowed to receive the  Azygos Process  of the
Sphenoid Bone.  3, Anterior Surface for the Car.
tilaginous Septum of the Nose.
  119.  Number of Teeth.—The Teeth of the Human Adult
when all present  in  the jaws,  number thirty-two.   And al-
though properly bones,  still they differ in three respects:
  1st, Organic Composition.
  2nd,  Time of Development  and Replacement.
  3d, Decay when fractured.
  120.  Organic Composition, Cementum, Dentine, Enamel,
Microscopic Structure  of  Enamel,  Development  of  Teeth,
Nasmyth's Membrane.—The  Teeth  are  composed  of three
substances:  a Cementum which forms a thin coating  on the
fano-s of the teeth, and which  thickens in advanced  life ; the
Dentine which resembles bone in its  external characteristics
and makes the largest part of the teeth, containing the prin-
cipal  vessels and  nerves of the  teeth;  and the Enamel, the
hardest substance in the human  body, which is a covering to

 118. From what does the Vomer derive its name ?  What two cavities does  it sep-
arate ? 119. How many teeth in an adult? In what respects do they differ from the other
bones of the body ?  120.  Of what substances arc the teeth composed? 
52
HITCHCOCK'S   ANATOMY
Fig. 61.
Fig. 62.
  Vertical Section of Human Incisor,  a,
the point where  the Gum is attached to
the Tooth.
Fig. 63.
Fig. 64.
  A View of an Incisor and of a Molar
Tooth, given by a Longitudinal Section,
and showing that the Enamel is striated
and that the Strise are all turned to the
center.   The  Internal Structure is  also
seen. 1, The Enamel. 2, The Ivory. 3,
The Cavitas Pulpi.
      A Vertical Section of an Adult Bicuspid,
    cut from without inwards; magnified four
    times.   1, 1, The Cementum which sur-
    rounds the Root up to the commencement
    of the  Enamel.   2, 2, The  Dentine of
    the Tooth, in which are  seen the greater
    Parallel Curvatures, as well as the position
    of the Main Tubes.  3, Apex of the Tooth,
    where the Tubes are almost perpendicular.
    4, 4.  The Enamel.  5, The Cavity of the
Pulp, in which are seen, by means of the Glass,
the Openings of the Tubes of the Dental Bone.


    all  the tooth  above the gums.

    This  is  a pure   white  sub-

    stance,  thickest upon  the top

    of the  crown, and  gradually

    growing thinner towards the

    gum,  where  it  disappears  al-

    together.   Under the micro-

    scope  it is  seen to be  mad.

    up of minute hexagonal fibers,

    one end of which  rests upon

    the  Dentine,   and  the  other

    forms the free surface of  the

    tooth.    These  tubes or fibres

    are  slightly   undulating  and 
AND  PHYSIOLOGY
53
from  go'ooth  to 54V .d  of an
inch  in diameter.   The en-
amel is also covered by a very
thin membrane, T5-f 5 Tst of an
inch in diameter, called  Nas-
myth's membrane.   This  is
a  " calcified" membrane and
can be seen  only with great
care, since it  is not acted up-
on  by the strongest  acids or
alkalies.
Fig. 65.
  A portion of the Surface of the Enamel
on which the Hexagonal Terminations of
the Fibres are shown ; highly magnified.
1 2, 3, Are more strongly marked dark,
crooked Crevices,  running between the
rows of the Hexagonal Fibres.
  121. Developmentof Teeth.
Temporary  Set. Permanent
Set.—The teeth in the human subject are not perfectly formed
at birth, but exist in the form of follicles or shut sacs, which
at the seventh or eighth month of infantile life, are developed
into teeth.   The process of dentition generally occupies from
one  to  three years, during  which time the temporary set, as
it is termed, make their appearance.   These  number twenty,
ten in each jaw, and between  the age of seven and fourteen
become loose, and are easily removed to give place to the per-
manent set which numbers thirty-two.  Generally, however,
the last tooth in each jaw does not make its appearance until
the twentieth year of life.

   122. A more accurate statement of dentition of the  tempo-
rary teeth shows that they appear at the following  ages:

           The  Incisors, from the 1th to the  10th montli.
           The Anterior Molars,   12th   "    13th    "
           The Canine Teeth,     14th   "    20th    "
           Posterior Molars,       18th   "   36th
123.  The permanent teeth appear as follows
  Describe each of the teeth.  What membrane completely covers the outside of the
tooth?  121. Illustrate the development of the teeth. 122. Give the time of appearance
jf the temporary teeth.  123. When do the permanent teeth appear ? 
54
HITCHCOCK'S   ANATOMY
             Incisors, from the 8th to the 9th year.
             Bicuspids,       10th  "   11th  "
             Canines,        12th  "   12£th "
             Second Molars,   12}th "   14th  "
             Third Molars,    17 th  "   19th  "

   124. Names  of Teeth.—A   third  set  of teeth  has  been
known  to  make its appearance;  also a tooth extracted  and
at once replaced  may become firm again at the. end of some
Lionths.
   The  names  and number of  the  permanent teeth  in  each
jaw, beginning at the posterior  part of the mouth,  are :
   2 Wisdom, 4 Molars, 4 Bicuspids,  2  Canine, 4 Incisors.
           I    c    d      e       f          g        h
    a, b, Incisors,  c, Canine, d, e, Bicuspids.  /, g, Molars,  K Wisdom teeth.

   125. Fracture of Teeth.—All the  bones  of  the  body, ex-
cept the teeth, when broken will become united again ; but if
the teeth  lose  a portion  of their  enamel, or  even if it be
cracked, the tooth  so injured at  once begins  to decay,  and
will be entirely consumed, unless  the disease be  checked by
artificial means.
 124. What is said about a third set?  Give the names of the permanent teeth.
125. What it the teeth are broken or cracked ? 
AND   PHYSIOLOGY.
55
  An Anterior View of the Os Hyoides,
1, The Anterior Convex Side 01 the Body.
2, The Cornu Majus of the Left Side.  S,,
The Cornu Minus of the same Side. Th*
Cornua were ossified to  the Body of th'«
Bone, in this specimen.
   126.   Hyoid  Bone. —The               fig. 67.
Hyoid Bone is the bone which
forms the base of the tongue,
and the  upper  extremity  of
the   trachea.     It   has  the
shape of the Greek  letter  U
(or  Upsilon)  and articulates
with no other  bones,  but is
completely  enveloped  by  the
soft  parts.    It  has  a consi-
derable  range of motion  in a
vertical  direction,  and hence
than eleven  pairs  of muscles.
   127.  Sternum,—The  Breast  Bone  is  flat,  about  eight
inches in length, one and a half in  width, and  is  located  on
the  median line of the body upon the  front portion of the tho-
rax or chest, articulating with the seven  upper  ribs  on  both
sides, and also with the clavicle.
    128.  Ribs.—There are twenty-four  ribs in  the human
  FIG. 68. 4-_/fsag%^                          Fig. 69.
gives
attachment to  no  less
                                     A View of the Upper Side of the First
                                   Rib of the Right Side, half the size of na-
                                   ture.  1, The Head. 2. The Tubercle.  3,
                                   Anterior Surface.  4, Groove for the Sub-
                                   clavian Artery. 5, Groove for the Sub-
                                   clavian Vein.  6, Anterior Extremity for
  A Front View of the Sternum. 1, First   the Cartilage. 7, Tubercle for the Scalenus
Piece.  2, Second Piece.  3, Ensiform Car-   Anticus Muscle.
tilage, or Third Piece. 4, Articular Face
for the Clavicle.  5, Articular Face for the First Rib. 6,  Articular Face for the Second
Rib.  7, 8, 9, 10, Articular Faces for the Last Five True Ribs.

  126. Where is the Hyoid Bone?  What Greek letter does it resemble ?  127. Describ*
the Sternum.  With what bones does it articulate ?  125.  Number of Ribs in man! 
56
HITCHCOCK'S  ANATOMY
Fig. 70.
  General Character of the other Ribs, seen on their Upper and  Under  Surface.   Th*
left hand figure is the Upper Face of the Rib. 1, Head of the  Rib.  2, Its Tubercle.
3, Anterior Extremity for the attachment of tho Costal Cartilage.  4, Groove for the Ar-
tery and Nerve. 5, Angle of the Rih. The right hand- figure is the Under Surface of
the Rib.  1, The Head.  2, Its Tubc-cle.  8, Anterior Extremity.  4, Groove for Inter-
costal Artery and Nerve.  5, Angle of the Rib.

body, which  are divided  into  two  classes, the true and  the
false, or those which  are closely united  with the  sternum,
and those which are remotely attached to it by  long cartilages.
They are attashed at  their posterior extremities  to the verte-
brae, and run downwards  and forwards, so  that  when elevated,
  Fig. 71.
Vertebral Column.
Ribs.
tatereostal Muscles. <
Clavicle.
...Third Rib.
Sternum.
Seventh Rib.
False Ribs. 
AND  PHYSIOLOGY.
57
they enlarge the cavity  of the chest.   The true ribs  are the
seven uppermost ones, and the false the five lower  ones,  and
are so arranged that they form a  cone with the apex at the
neck.   The two lowest ribs are sometimes called " floating,';
because they are only attached to the vertebrae.
Fig. 72.
   129.  Clavicle.—
The Collar Bone is the
commencement   of
the upper extremity.
It is one  of the class
of  long  bones   ex-
tending   from   the     A_ Anterior view of the  Clavicle  of the Right
highest point of  the  Side- !. The Anterior Face  of the Body of the Bone.
  &  ii          2>  Origin of the Clavicular portion of  the Sterno-
SCapula tO the Upper  cieido-Mastoid Muscle.  8, The Sternal  Extremity of
part Of the Sternum,  «»e Bone.   4, The Acromial Extremity  of'the Bone.
r                   '  5, Articular Face for the Acromion Process of the Scapu-
and  bears a  partial  la.  6, Point of Attachment of the Conoid Ligament
      it       ,    .i    7, Point of Attachment of the Rhomboid Ligament.
resemblance  to   the
Italic  letter  F.   The name  is from the  Latin  Clavis,  "a
key,"  since it remotely resembles an antique key.
   130. Scapula.—A  large,  flat, and  triangular bone upon
the  upper part  of the  back,  and forming  the shoulder,   is
called  the Scapula, or  Shoulder Blade.   It has  a  high and
narrow ridge  running through  its longest  diameter,  which  is
the bone  so distinctly felt upon the shoulder and  upper part
of the back.   Its only articulations are with the clavicle and
humerus,  the posterior part being kept in its place by mus-
cles  and ligaments.  (Fig. 73, p. 58).

   131. Humerus.—The Humerus is  the  bone  of the  upper
arm or shoulder.   (Fig. 74, p.  58.)   It is a long bone with
a cylindrical  shaft,  and has a rounded head for  its upper  ex-
tremity.    The lower  extremity is flattened from before back-
 What two classes are they divided  into?  What do they all unite with behind?
129. What two bones does the Clavicle unite with ?  180. What is the general outline of
the Scapula ?  Where is it located ? What are its only articulations ? 131. What is the
bone of the upper arm ? 
53
HITCHCOCK'S   ANATOMY
Fig. 73.
Fig. 74.
  A Posterior View ol the Scapula of the
Left Side. 1, Fossa Supra-Spinata. 2, Fos-
sa Infra-Spinata.  3, Superior Margin.  4,
Coracoid Notch.  5,  Inferior Margin.  6,
Glenoid Cavity.  7, Inferior Angle. 8, The
Neck and Point of Origin of the Long Head
of the Triceps Muscle.  9,  Posterior,  or
Vertebral Margin.  10,  The Spine.  11,
Smooth Facet for the Trapezius Muscle.
12, Acromion  Process. 13, Nutritious Fo-
ramen.  14, Coracoid Process.  15, Part of
the Origin of the Deltoid Muscle.
                                    An Anterior View of the Humerus of the
                                  Right Side.  1, The Shaft, or Diaphysis of
                                  the Bone.  2, The  Head.  3, Anatomical
                                  Neck.  4, Greater Tuberosity.  5, Lesser
                                  Tuberosity.  6, The Bicipital Groove. 7,
                                  External Bicipital Ridge  for the insertion
                                  of the Pectoralis Major.  8, Internal Bici-
pital Ridge.  9, Point of insertion of the Deltoid Muscle.   10, Nutritious Foramen.
11, Articular Face for the Head  of the  Radius.   1'2, Articular Face  for the Ulna.
13, External Condyle.  14, Internal Condyle.  15, 16, The Condyloid Ridges.   17,
Lesser Sigmoid Cavity.
wards, and so formed  into grooves and  elevations  that it  ar-
ticulates with the ulna in essentially the same manner  as  the
two portions of a door hinge.

   132. Fore-arm.   The Ulna.—There  are  two bones  in  the
forearm, one of which only is articulated  with  the humerus,
and the other to the bones  of the wrist alone, in order to  al-
low the rotation  of  the hand upon the bones  of  the forearm,
  What is the shape of the lower, or ulnar  articulation ?
forearm ?  Why are there two instead of one ?
132. How many bones in th« 
AND  PHYSIOLOGY.
59
 as if they constituted a pivot;                Fig. 7e
 an instance of which is seen in
 the turning of a screw, or in
 the unlocking of a door.   Of
 these two bones the Ulna arti-
 culates with the humerus, form-
 ing only a ligamentous  union
 with  the  bones of  the  Avrist.
 It is prismoid in form, and is
 of a hooked shape at its  up-
 per  extremity,  so  that  it
 makes the union between  it-
 self and the  humerus a very
 secure one.  The word ulna
 is a Latin term signifying  an
 ell,  because  the  forearm  in
 early times was used for that
 measure.
   133.  The  Radius___The
 Radius  is  the  mate  of  the
ulna.  Its  upper extremity is
the smallest,  and the lower
the largest, since its  only true
articulation is  at the wrist.
A firm  membrane,  however,
unites this  bone to its fellow  nearly its whole length. It prob-
ably derives its name  from the fact  that it measures the ra-
dius of a circle  which may  be described  by  the  hand  about
the elbow as a center.
  134. The Carpus.—The bones of  the Carpus or Wrist are
eight in  number,  are small and irregular, and have the gen-
eral disposition of two rows.  The first row, commencing with
the one nearest the thumb, contains the Scaphoid, Semilunar,
  In what operations do we need the two bones of the forearm ?  Give thje derivation of
ulna.  133. What is the mate of the ulna?  Where does this articulate? What is the
derivation of its name? 134. How many bones in the wrist? Give their names.
  Bones of the Forearm.  1, The XTlna.
2 and  3, The Sigmoid Notches.  4, The
Olecranon Process.  5, Coronoid Process.
6, Nutritious Foramen. 7. Ridge for at-
tachment of Interosseous Membrane. 8,
Capitulum Ulnae. 9, Styloid Process.  10,
Shaft of the Radius.  11, 12 and 13, Head,
Neck, and Tuberosity of Radius.  14, Ob-
lique Line for muscular attachments.  15,
Styloid Process. 
60
    HITCHCOCK'S   A N A T O M Y

Fig. 76.                             Fig. 77.
  A Posterior View of the Articulations
of the Bones of the Carpus in the Right
Hand.  1, The Ulna. 2, Tho Radius.  3,
Inter-Articular Fibro-Cartilage.  4, Meta-
carpal Bone of the Thumb.  5, Metacarpal
Bone of the First Finger.  6, Metacarpal
Bone of the Socond Finger.  7, Metacar-
pal Bone of the  Third  Finger.   8, Meta-
carpal Bone of the Fourth Finger. S, The
Scaphoides. L. The Lunare.  C, The Cu-
neiforme.  P, The Pisiforme.  T, T, Tra-
pezium  and Trapezoides. M, The Mag-
num. U, The Unciforme.
  An Anterior View of the Left Hand.
1, The Scaphoides.  2, The Lunare.  3,
Tho Cuneiforme.  4, The Pisiforme. 5,
The Trapezium.  6, Groove for the Flexor
Carpi Radialis Tendon.  7, The Trape-
zoides.  8, The Magnum.  9,  The Unci-
forme.  10, 10,  The Five Meta-Carpal
Bones.  11, 11, First Row of  Phalanges.
12, 12, Second  Row of Phalanges.  13, 13,
Third Row of Phalanges.  14.  First Pha-
lanx of the Thumb.  15, Last Phalanx of
the Thumb.
Cuneiform, and Pisiform.    The second in the same order, the
Trapezium, Trapezoid, Magnum, and Unciform.

   135.  The  Metacarpus. — The  Metacarpus  contains  five
bones.   Each of these  articulate with  the carpus above,  and
the phalanges below, being found in the  space known as  the
palm or body of the hand.

   136.  The  Phalanges.—The Phalanges are the  bones  of
the thumb and fingers,  two  in  the former, and  three in the
latter, making fourteen in each hand.
 135. Describe the Metacarpal  Bones.  What part  of the hand  do  they occupy?
136. How many Phalanges in the thumb, and how many in  each finger ?  What is the
whole number of them ? 
AND PHYSIOLOGY.
61
  137.  Bones of the Pelvis.—The bones  of the  Pelvis are
the  two Innominata or  nameless  bones,  and the Sacrum and
Coccyx, which have already been described.  (Fig. 78.)

                           Fig. 78.
   138. Tlie lnnominatum,  Ilium, Ischium, Pubes.—Each
lunominatum presents the largest surface of any bone  in the
body.  They  are  irregularly  flat bones  and  situated  just
beneath the abdomen, to the organs of which they give  firm
support by their broadly-expanded surface.  In  young skele-
tons they are divided into three portions, and hence they are
described in the adult as made up of three parts,  although no
line of division can actually be seen.   The Ilium constitutor
the broadly-expanded  portion  usually known as  the hip cr
haunch.   The Ischium, from the Greek signifying to "hold"
or "retain," is the heavy portion projecting downwards,  and
that point on which the body rests, when in a sitting posture.
 137. How many bones in the Pelvis, and what are  their names?  138. Describe the
lnnominatum. Into how many parts are they divided in  young animals? Describe
the Ilium and the Ischium. 
62
     HITCHCOCK'S   A X A T O M _

Fig. 79.                                 Fie
  Outside of the lnnominatum of the Right Side.
1, Dorsum of the Ilium.  2, Ischium. 3,  Pubis.
4, Crest of the Ilium.  5, Surface of the Gluteus
Medius.  6, Surface for the Gluteus Minimus.
7, Surface for the Gluteus Maximus.  8, Anterior
Superior Spinous Process. 9, Anterior Inferior
Spinous Process.  10, Posterior Superior Spin-
ous  Process.   11,  Posterior Inferior  Spinous
Process.  12, Spine of the Ischium. 13, Greater
Sacro-Sciatic Notch.   14, Lesser Sacro-Sciatic
Notch.  15, Tuber Ischii. 16, Ascending Ramus
of the Ischium.  17, Body of the Pubis.  18, Ra-
mus of the Pubis.  19, Acetabulum. 20, Thyroid
Foramen.
                 An Anterior View of theFemuro
               the  Right Side.  1, Depression fin
               the Round Ligament.  2, The Head.
               3, The Neck.  4,  Trochanter Major.
               5, Trochanter Minor.  6, Surface for
               the Capsular Ligament.  7, Shaft o(
the Bone. 8, The External Condyle. 9, The Internal
Condyle. 10, Surface for the Patella.
The Pubis is the most  central and  anterior  portion.    These
three  divisions unite at the point known as the acetabulum or
receptacle for the head  of the  femur, which is a perfect hemi-
spherical cup  lined with cartilage.
   139. The Femur.—The Femur is nearly two feet in length,
and consequently the  longest  bone in  the body,  commonly
known as  the  Thigh Bone.   At  its  upper portion it makes a
  139. What is the average length of the Femur ?  Give its general features. What u
the longest bone in the body? 
AND  PHYSIOLOGY.
03
Budden bend inwards, forming the neck of the bone, the ter-
mination of which is hemispherical, in order to articulate with
the innominatum,  forming  the ball  and  socket  joint.   Its
lower extremity  has two large condyles or  processes, for the
purpose of giving attachments to  the ligaments  of the knee,
and articulating with the tibia.
   140.  The Patella  —Or Knee Pan is the      Fig. si.
i.rgest sesamoid bone in the body.  It arti-
culates with the  femur, and lies imbedded in
the extensor tendon of the thigh.  The chief
value  of  this bone  is  to give a  change  of
direction to the force of the muscles  which
move the lower bones  of this  extremity Ave
are now describing.   Patella  in Latin signi-   An Anterior VIew, ol
fies a "plate," and hence the name of this thePateia.  1,2,sur-
                         -  .   ,.             face for the Quadriceps
bone, because 01 its rounded outline.         Femoris Tendon.  3,
                                             Lower Extremity and
   141. The  Tibia.—That portion of the  Point  of origin of the
              ...     .   .        ....   Ligamentum Patellae.
lower  extremity  below the knee,  which  is
properly the leg, has  two  bones  called crural for its frame-
work.  The largest  of these is the Tibia (Fig. 82,  p.  64.)   It
is somewhat  triangular in its general outline,  having  its
upper  extremity  depressed in two places  for  the  reception
of the condyles of the femur.   Besides  the   femur  above,
it articulates with  the  fibula and astragalus  below.   The
name  tibia is  given to the bone, since it resembles, though
remotely, the ancient Phrygian flute.
   142. The  Fibula.—The Fibula is the other bone  of  the
leg, long  and  slender.   It  articulates at  each  end  with  the
tibia.   The  meaning  of the  Latin  fibula,  is  a  "pin,"  or
fastening  of a clasp, owing to its  slender form.   The lower
extremity of  this bone, and also that of the tibia,  forms what

  140. Describe the Patella or Knee Pan.  In what is it imbedded? 141. What is tha
Leg?  What are the two bones of it? Which is the largest and consequently most im-
portant one ?  142. Give the general description of the Fibula.  What compose the ex-
ternal and internal Malleoli ? 
64
HITCHCOCK'S   ANATOMY
Fig. 82.
                            A View of the Upper Surface of the Left
                          Foot.   1, The Astragalus on its Upper
                          Face.  2, Its Anterior Face, Articulating
                          with  the Naviculare.  3, The Os Calcis.
                          4, Naviculare, or Scaphoides.  5, The In-
                          ternal Cuneiform.  6, The Middle Cunei-
                          form.   7, The External Cuneiform.  8,
                          The Cuboid Bone.  9, 9, Metatarsal Bones.
                          10, First Phalanx of the Big Toe.  11, Sec-
                          ond Phalanx of the Big Toe. 12, 12, 13,
13, 14, 14, The First, Second and  Third Phalanges of the other Toes.
  Right Tibia and Fibula.  1, Tibia.  2
and 3, Inner and Outer Tuberosity.   4,
Spinous Process.  5, Tubercle for  attach-
ment of Muscles of the Thigh. 6, Edge of
Tibia.  8, Internal Ancle. 9, The Fibula.
10 and 11, Extremities of T'ibula.
are known as the external and  internal  malleolus, or the two
long  projections on each side of the ancle.

   143.  The Tarsus.—The  Tarsus is  made  up  of  seven ir-
regular bones,  forming  the instep of  the foot.   The  Astra-
galus is  of a  cubical  form  (so named from its  resemblanca
to the die, used in  games of chance)  and supports  the tibia
alone.   The Os Calcis,  meaning the bone of the heel, is the
largest of the bones of the tarsus,  and  is irregularly  cubical
  143. How many bones make up the Tarsus?  Why is the uppermost called the Astra-
galus ? Which is the largest of these bones ? 
AND  PHYSIOLOGY.
65
in form, making, by a decided  projection, the heel.   Directly
beneath and  anterior to the last two, are found the  Cuboid
(cube-shaped) and  the Scaphoid (boat-shaped),  and anterior
to these the  three  Cuneiform (wedge-shaped)* articulating
with the metatarsal bones in front.
   144.  Metatarsal  Bones.—These are five  in  number, and
correspond with those in the metacarpus, except  that  the one
in the first toe is of equal length with the others, and does net
admit of so free motion as  that of the thumb.
   145.' The  Phalanges.—The Phalanges of  the foot  are also
like those of the hand, except that in the foot the first row  is
the longest, while in the hand  it is in the third row or second
finger.
   146.  Sesamoid Bones.—Besides the bones already men-
tioned, there are frequently found  in stout adult  men small
bones, or portions of bony matter  called Sesamoid  Bones,
from their  resemblance to  the  Sesamum,  a kind  of bean.
And although they are not constant either in individuals,  or
in the  same  places  in the  individual, yet  anatomists are
accustomed  to reckon  eight, or  four  pairs  as the  normal
number.   They are all found  enclosed  in tendons, and serve
like  the  patella  to change the direction  of  motion.    They
are  found at the  point  where  the tendon  glides over the
joint made  by the phalanges and metatarsus  of  the foot,
and the metacarpus of the  hind, in the  tendon  which  plays
over the under surface of the  cuboid bone in the  foot; and
also  in  the  tendons that  glide over the lower  condyles of
the femur.
   147.  Bones  of the  Ear.—In  the  Ear  are  three  bones
which will be more  appropriately described  with the  organ
itself.
   148.   Number of  Bones.  Single  Bones.—Of  the  246

 144. How many Metatarsal Bones?  145. How many  Phalanges of the Foot? How
do they differ from those of the hand ?  146. Describe Sesamoid Bones. How many are
there, and where are they generally found ? 147. How many bones of the Ear 1 
66
HITCHCOCK'S  ANATOMY
bones found in the human body, all but thirty-four are found
in pairs,  or  one upon  each side of the  body.   The  single
bones are the  frontal,  occipital,  ethmoid, sphenoid,  vomer,
mandible,  hyoid, sternum,  twenty-four vertebrae,  the sa-
crum and, the coccyx.
                  SYNDESMOLOGY.

         DESCRIPTION  OF  THE  LIGAMENTS.

   149. Rinds of Articulation.—The modes or  manner  of
connection between the different bones of the body are three :
Synarthrosis, Amphiarthrosis, and Diarthrosis.   The first  of
these  modes, means  the joining  of such  bones as  have no
motion between  them ;  the  second, a joint with the aptitude
for movement between the immovable synarthrosis on the one
hand,  and the movable diarthrosis on the  other; the third, a
movable articulation, which constitutes by  fir  the  greater
part of the joints of the body.
   150. Sutura, Ilarmonia, Schindylesis,  Gomphosis.—Of
Synarthrosis there are  four varieties :  first, Sutura,  the  ar-
ticulation  between  the  bones  of the  skull by ragged inter-
locking edges ; second, Ilarmonia, that between the two upper
maxillaries,  where  the  bones with  comparatively  straight
edges are simply placed edge to edge;  third, Schindylesis,  or
the  joint between the  vomer  and sphenoid, where  the ex-
panded edge of one bone is fitted into a corresponding groove
in the other; fourth, Gomphosis, the articulation of the teeth
with the jaws, and so named since it  resembles the  manner
in which a common nail is driven into a plank.
 148. How many bones in the human body are found in pairs? Give the names of the
unmated bones.  149. How many modes of connecting the bones together ? Describe
each.  150. Give the peculiarities of Sutura, of Ilarmonia, of Schindylesis, and of Gom-
phosis.  Give an example of the latter. 
AND  PHYSIOLOGY.
67
   151.   Symphyses.—Of Amphiarthrosis there is but  one
k**d,  the Symphyses, or  the  apposition  of  two bones  with
simply  cartilage between.   Examples of this  are  the  arti-
culations of the  vertebrae, and  the ossa- pubis.

   lo_r.   Arthrodia,  Giislymus, Enarthrosis.—Of Diarthro-
sis there are three v. rbties: Arthrodia, Ginghymus, and  En-
arthrosis.   Arthrodia is a slightly  movable joint, as of th3
wrist and ancle bones,  or  the radius and  ulna.   Ginglymus
is the common  hinge joint,  where  the degree  of movement
is very considerable, but only in  two  directions.   The  best
example of this is  in the knee.  Enarthrosis is the ball and
socket joint, that admits of movement in all  directions.   The
only cases  of this articulation are  in the shoulder, hip, and
thumb.

   153.  Anatomy  of  the Articulations.—In synarthrosis
there is simply  a membrane interposed between  the two bones
which  keeps them  in  their  places.  In  amphiarthrosis the
two extremities are partly covered with cartilage, lined by
synovial membrane, and partly connected by the interosseous
ligaments, or by an elastic fibro-cartilage which adheres  to
both  edges  of the boi-es.   In diarthrosis  especially, as  it is
exhibited in  ginglymus,  the  general outline of the bone i3
quadrilateral, upon each edge of which is found a  ligament.
The lateral ones, however, are the main supports of the joint,
while the anterior and posterior ones  are  thin and  a  part of
the time loose, which are only of  service to  determine the
amount of movement  in  the  joint.   An  example  of  this is
seen  in the fingers, since they can only be extended  so  as
to lie  in  the axis  of  the metacarpal  bones.   The  reason
why  they can not be  bent back  upon the  dorsal  surface ot
the hand is that the anterior ligament does not  admit of suffi-
 151. Describe the Symphyses. Give an example. 152. Give the three varieties of Diar-
throsis.  Give an example of Arthrodia, Ginglymus, and Enarthrosis. 153. What are
the component parts of the different articulations? Give the mode of articulation o)
the fingers.  Why ean not the finger be bent upon the back of the hand ? 
68
HITCHCOCK'S   A N A T O M Y
cient  movement  in  that  direction.   In  the knee, however,
there  are thirteen ligaments.
  154.  Motions  of  the Joints.—The motions of the joints
may be  comprised  under  four principal divisions :  Gliding,
Angular movement,  Circumduction, and  Rotation.
  155.  Gliding.—Gliding  movement  is where  the  bones
simply slip  over  one another  in the movement of the  joint,
and exists to a greater or less extent in all the joints.
  156.   Angular.—Angular  movement  may be  performed
in four  directions :  forwards  and  backwards,  called flexion
and extension, and  inwards and outwards, called adduction
and abduction.   A joint, as the finger,  is  said  to be  flexed
when  it  is  bent  upon  itself, that  is  upon  the  palm of the
hand, and extended when it is stretched to  its fullest extent,
or as in the  finger, when it is made straight  with the bones of
the  fore-arm.   Adduction  means the  bringing of  one of tho
extremities towards  the body,  or  its fellow, while abduction
has the reverse signification.
  157.' Circumduction.—Circumduction can  be  performed
only by the ball and socket joints.   It  consists in  carrying
the limb  about  the joint  in  a circular plane, or  in other
words, describing a circle about the joint as  a center.
  158.  Rotation,—Rotation is the movement of a bone upon
its own axis.   A slight rotatory movement can be effected in
the joints of the shoulder  and hip, but  tho best  instance is
that of the radius rotating against the articular head of the
humerus, producing  the subdivisions pronation and  supina-
tion.  Pronation consists in rotating the  fore-arm  so that the
palm  of the hand shall  be downwards, and Supination the
reverse.   Rotation  is also observed in the movement of the
atlas  upon the pivot of the axis.

  154. What are the four motions of the joints ? 155. Describe the Gliding movement.
156. In what four directions can Angular movements be ?  157. What is  Circumduction ?
158. Describe Rotation. What is Pronation and Supination ? 
AND  PHYSIOLOGY.                6£
   159. Structure of
Ligaments.    Ar-
rangement of Liga-
ments.  Capsular
Ligament.  Round
Ligam ent.—The
bones  are  firmly
hound  together  by
ligaments.     These
are   for   the  most
part bands of white
glistening fibres,  as
firm as steel,  which
are   composed   of
white  fibrous    tis-
sue.  They are gen-
erally  very   short,
and  attached  only
to the enlarged  ex-
tremities  of   the
bone.   In most  of
the  joints, and  es-
pecially the  gingly-
mus, the  ligaments
are  arranged in a
cross shape upon the
sides of the  bones,
so that one bone may
glide freely over the
extremity   of   an-
other, as  one  half
of  a  door   hinge
moves upon its other
half.   In  other  in-
stances the ligament
surrounds  the whole
Fig. 84.

	■■ig».j».jg,-!»j:
}	;; ■■#■%■:■&';<;
	y ,__p <s* -•■■/,i._...
	v*-'.,; -■.-..•- 4g)'\
	

  A magnified View of a Vertical section of Cartilage
from a new-born Rabbit, showing the progress towards
ossification.  1, The Ordinary appearance of Tempo-
rary Cartilage. 1'. The same, more highly magnified.
2, The Primary Cells beginning to  assume the linear
direction.  2', The same, more highly magnified. 3i
The Ossification  is extending in the  intercellular
spaces, and the rows of cells are seen resting in tho
cavities so formed, the  Nuclei being more separ-
ated than  above.  8',  The same,  magnified mora
highly. 
HITCHCOCK'S  ANA T O 31 V
  An Anterior View of the Ligaments of    Ligaments from Shoulder-Joint  1, The
the Pelvis.  1, The Lower part of the An-   Superior  Acromio-Clavicular  Ligament.
terior Vertebral Ligament.  2, The Sacro-   2, The Coraco-Clavicular Ligament.  3,
Vertebral Ligament.  3, The Ilio-Lumbar   The Coraco-Acromial Ligament.  4, The
Ligament. 4, Tho Anterior portion of tho   Coracoid Ligament. 5, The Capsular Liga-
Sacro-Iliac Ligament.  5, The Obturator   ment of the Shoulder-Joint. 6, The Liga-
Ligament. G, Pouparfs Ligament. 7, That   mentum Adscititium, or Coraco-Humcral
portion of the same  which is known as   Ligament.   7,  The Tendon of the Long
Gimbernat's Ligament. S, The Capsular   Head of the Biceps Muscle, issuing from
Ligament of the Hip-Joint.  9, The Ac-   the Capsular Ligament.
cessory Ligament of the Hip-Joint.


joint, making it a shut sac, thus performing the double office

of keeping the  two ends in contact, and of  holding the lubri-

cating  fluid  in  the joint.    In  addition to  these, there is  in

the ball and socket  joint another kind of ligamentous attach-

ment between the two bones, called the  round  ligament,  or

Ligamentum Teres.   This i3  a  bundle of  ligamentous  fibres

in the form  of  a cord,  which  is inserted  into the summit  of

the rounded head of the bone, and also in the bottom  of the

cup-shaped  cavity that receives the head.   This  is somewhe;

lax ordinarily, but not so much so  but that it keeps the  head

from  slipping out  of its socket, and at the same time allows

the most perfect freedom of motion.

  159. What are  the  Ligaments ? To what part of tho  bones are  they generally at-
tachc-d?  How are they arranged in Ginglymus joints ?  Why are they sometimes found
in the form of a shut sac?  Describe the round ligament. 
AND   PHYSIOLOGY.                   VI
Fig. 87.
Fig. 88.
  A Lateral View of the Ligaments of the Hip-
Joint and Pelvis.  1, The Posterior Sacro-lliac
Ligament of the Pelvis.  2, The greater Sacro-
Sciatic Ligament.  3, The Lesser Sacro-Sciatic
Ligament. 4, The Greater Sacro-Sciatic Notch.
5, The Lesser Sacro-Sciatic Notch. 6, The Co-
tyloid Ligament around  the  Acetabulum.  7,
The Ligamentum Teres.  8, The Line of At-
tachment of the Capsular Ligament of the Hip-
Joint,  posteriorly.  The  Ligament has been
removed, in order to show the Joint.   9, Tho
Obturator Ligament.
  The Right  Knee-Joint laid open,
1, The Lower End of the Femur cov-
ered by its Articular Cartilage. 2, The
Anterior Crucial Ligament.  3, The
Posterior Crucial Ligament.  4, The
Transverse Fasciculus  adhering to
the Semilunar  Cartilages.  5, The
Point of Attachment of the Ligamen-
tum Mucosum, the rest of it has been
removed. 6, The Internal Semilunar
Cartilage. 7, The External Semilunar
Cartilage.  8, A part of the Ligamen-
tum Patellae turned downwards.  9,
Its Bursa laid open.  10, The Supe-
rior Peroneo-Tibial Articulation. 11,
The Interosseous Ligament.
   160.  Aid of  Atmospheric  Pressure.—Atmospheric  pres-
sure also helps  to keep  the  bones together.   For  since  the
projection  of one member so accurately fits the  depression in
the  other,  and  as the lubricating fluid  makes  the  coupling
most  perfect, the pressure of the atmosphere  assists  not a
little to keep the parts together.
   161. I :i t e r - a r t i c u 1 a r C a r t i I a g e.—Another arrangement in
the joints i3  not a little singular, and well adapted  to its pur-
pose.   This  is an interarticular cartilage  in the knee  called
semilunar,  or a small disc of cartilage  which  lies  loosely  be-
  1G0. What besides the ligaments helps to keep the bones together? 161. Describe tha
interarticular cartilage and its use.
4 
    h i t 0h c o 0 k ' s  an a t o m y

Fig. 89.                          Fig. 90.
  An Anterior View of the Ligaments of
the VertebriB and Ribs.  1, The Anterior
Vertebral Ligament. 2, The Anterior Costo-
vertebral Ligament.   3, The  Internal
Transverse Ligament.  4, The Inter-Ar-
ticular Ligament,  connecting the Head
of the Rib  to  the Intervertebral  Sub-
stance.
Fig. 91.
  A View of the Articulation of the Lower
Jaw, given by sawing through the Joint.
1, The Glenoid Fossa.  2, The Tubercle
for the Condyle  in its Forward move-
ments.  8, The Inter-Articular Cartilage.
4, The Superior Synovial Cavity.  5, The
Inferior Synovial Cavity.  6,  The Inter-
Articular Cartilage  removed from  the
Joint and seen from below.

tween the bones.   The design of it  is to distribute  the  fric-

tion over a larger surface, as well as to diminish it.

                                        162.    In  Fig.  90  we see

                                     the  mode of attachment  be-

                                     tween the vertebrae  and  ribs

                                     which  is that  of  three  dis-

                                     tinct  ligaments  to  each  rib,

                                     besides  one common  to  each

                                     pair  of ribs.   Fig.  91 shows

                                     the  anatomy  of the  elbow-

                                     joint.    Here  are   no  less

                                     than four  distinct ligaments.

                                     We  see  in  Fig.  92  the liga-


                                      An Internal View of the  Elbow-Joint.
                                     1, The Capsular Ligament.  2, 2, The In-
                                     ternal  Lateral Ligament.  3, The  Coro-
                                     nary Ligament.  4, The Ligamentum Te-
                                     res.  5, The Interosseous Ligament.  6,
                                     The Internal Condyle, which conceals the
                                     Capsular Ligament behind.
 162. Describe the ligaments in Figs. 90, 91, 92 and !
eated?
163. How are the joints lubrJ. 
AND  PHYSIOLOGY.                   73
ments which unite the lower
end of the  fibula to the  tibia
and the tarsal  bones,  and in
Fig. 93 the ligaments of the
foot.
   163.  Synovial  Membrane
and   its   Secretion. — The
labrication  of  the  joints  is
effected  by means  of a  thin
membrane  lining  their  cavi-
ties  which  secretes  an  oily
substance called the  Synovia,
(Fig.  94,  p. 74),  that is  con-
stantly applied to the oppos-
ing surfaces.    In health the
action of  the joint stimulates
this membrane to the  secre-
tion of a proper  amount of
                                Fig
Fig.  92.
  A Posterior View of the Ankle-Joint ol
the Left Side.  1, The Interosseous Liga-
ment of the Bones of the Leg.   2, The
Posterior Inferior Ligament  connecting
the Tibia and Fibula.  3, The Transverse,
or Long Fibres of the  same Ligament
4, The Internal Lateral Ligament.  5, The
Posterior Fasciculus  of the External Lat-
eral Liu'ament.   6, The  Middle Fascicu
lus of the same.  7, The Synovial Capsule
8, The Os Calcis.
   A Vertical Section of the  Ankle-Joint and Foot of the Right Side.  1, The Tibia.
2, The Astragalus. 3, Os  Calcis. 4,  The Scaphoides.  5, The Cuneiforme  Internum.
6, The Metatarsal Bone of the Great Toe.  7, The  First Phalanx of the Great Toe.
8, The Second Phalanx of the Groat Toe.  9, The Articular Cavity between the Tibia
and Astragalus, with  its Articular Adipose Matter.  10, The Synovial Capsule between
the Astragalus and  Calcis.   11, The  Calcaneo-Astragalian  Interosseous Ligament.
12, The Synovial Capsule between the Astragalus and Scaphoides.  13, The  Calcaneo-*
Scaphoid Ligament.  14, The Calcaneo-Cuboid  Ligament. 15, The Synovial Capsule
between the Scaphoides and Cuneiforme Internum.  16, The Synovial Capsule between
the Cuneiforme Internum and the  First Metatarsal Bone.  17, The  Metatarso-Pha-
langial Articulation of the Great Toe, with the Sesamoid Bones below.  18.  Th* Pha.
langial Articulation of the Great Toe. 
74
H I T (' 11 <' < > < '■ K ' S  ANATOMY
Fig. 94.
 An Internal View of the Ankle-Joint of
the Right Side.   1, Internal Malleolus.
2, 2, Part of the Astragalus, the rest being
concealed by Ligaments.  3, Os Calcis. 4,
Scaphoides.  5, Internal Cuneiform Bone.
6, Internal Lateral, or Deltoid Ligament
7. The Synovial Capsule, covered by a few
Fibres of a Capsular Ligament.  8, Tendo Achillis.  A small Bursa is seer.
between this Tendon and  the Tuberosity of the Os Calcis.
synovia,  the superabundance
of which  (when it is present)
is removed by  the  absorb-
ent vessels.  This lubricating
fluid, however, is not  poured
out  directly upon  the ends
of the bones, but upon smooth
and  elastic cartilage,  which
is found  in every joint,  not
only for furnishing  a  smooth
articular  surface, but  also to
diminish  the force of jars by
its elastic character.
FUNCTIONS  OR USES  OF  THE  BONES
   104.   The uses  of the bones may be classed under  three
divisions :
   First,  for a framework to the whole system,
   Second,  to  furnish  points  of attachment  to muscles and
ligaments.
   Third,  to protect the softer parts.
   165. A Framework. Ligaments used as  Braces  and  Pins.
-—Exactly as a human architect plans and constructs a frame
to the house, so the  Great  Architect has formed  the bones.
Each bone is fitted exactly to the position,  size, and use  of
the part where it is placed, and nowhere can a supernumerary-
bone be found.   In the house to be built, braces  and joining
pins  must  be  employed, and those  generally of  a tougher
material than the frame itself.   So in the human body, liga-
  Why is cartilage useful in the lubrication of joints?  164. Give the uses of the bones
as classed above. 165. Corcipara the bones and ligaments with the timbers, braces  and
pins of a house. 
AND  PHYSIOLOGY.
75
ments and  cartilage  exist wherever  two opposite extremities
need strength and support to keep them in their places.  In
the railway locomotive immense strength  is required, and  at
the same time perfect freedom of motion in certain positions,
all  of  which is effected by  the  ponderous bars,  levers and
wheels, perfectly secured by bolts, keys and screws.   But  in
the human frame by how much more simple  means is the
same  end  secured.   No angular  or  cylindrical  couplings
secure the  human joints,  though beautifully adapted to pro-
duce movement in every direction, and  no attention or care is
necessary  to lubricate  and preserve  in  good condition the
working parts  of this machine, but a few tough fibers and
membranes, secure at once  in  a most  perfect manner every
portion of  the frame, and provide at the same time means foi
its  lubrication.
   166. Use of  the Anomalous Forms of  Bones.—The  bones
are fitted  for  the  attachment of  muscles  and ligaments.
Hence  it  is that  they are of  such  anomalous and   curi-
ous forms,  apparently  constructed  without design or  pur-
pose.   But as we study them, and understand the various
motions which they must  perform,  as well as the  organs
which  many of them must protect,  or provide  space for, we
find that it is impossible to improve in the slightest degree on
the construction of the skeleton.   The  size,  the  form, the
quality of  material,  the exact position  of every process, curve
and foramen of the  bones, and the  manner  in which  all are
arranged, are most wisely adapted  to their  functions and to
the happiness of the vertebrated race.
   167.  Reason  why the Long  Bones are  Tubes.—In thi»
connection should be mentioned  the  reason why  the long
bones are hollow.   It is for the same cause that the stems of
grasses, grains, and  many other vegetables are hollow  cylin-
ders, instead of solid rods : to secure  great strength with as

  166. Why arc the bones of such peculiar shapes? 167. Give the reason why many of
the bones are hollow. 
76
HITCHCOCK'S   ANATOMY
 little material as  possible.   For  example, were  the human
 femur a solid rod, instead of a hollow cylinder, as it now is,
 it would require a bone twice the diameter of the  present one
 t) be  sufficiently strong  for the  purposes required  of it.
 Hence  were the whole skeleton constructed on this principle,
 it would be so cumbersome and heavy that it would require a
 larger  amount of muscle, making  the body  unwieldy,  and
 thus deprive it of its rapid and easy motion.
   168.  Protection given to the  Brain.   Use  of  the Diploe,
 Reason for  several  Bones   in  the Skull.—The bones af-
 ford much  protection  to  all  the  enclosed and adjacent or-
'gans.   In  the bones  of the  head, for  example, how perfect
 the  guard over the  nervous center.   Here are three means
 for protection, two plates of bone,  and an  intervening  cel-
 lular space.   The outer  table being  very  tough  presents
 a substance  somewhat yielding to blows inflicted  by pointed
 substances,  and  even  if the blow be so severe as  to  cause
 fracture,  this can not extend so  far  as  in a  hard  and
 brittle material.   And the intervening space or diploe very
 materially deadens the force of any  shock   given to  the
 outside of the head, precisely as the  springs  of  a carriage
 prevent the unevenness of the  road from giving the  same
 sudden  jolt to the body that is communicated to the wheels.
The inner  table  is  necessarily brittle, since  the  brain  de-
 mands  the  firmest possible support.  But why is the  skull
 made up of several bones instead of one ?  In the first place a
 more symmetrical growth can be effected, provided  the points
 of increase are numerous, and especially so since in early life,
 while the growth is going on, there is a thin layer of cartilage
 between the edges of  each bone, thus allowing  all necessary
 motion; secondly, because a  fracture can  not extend further"
 than a suture, as all the vibrations are overcome by the inter-
 position of  any soft substance  like  cartilage.   And for this

  163. How do tho bones afford a protection to the softer parts?   What is the
 use of the dipl6e in the bones of the skull?  State the reason of several bones in
 the skull. 
AND  PHYSIOLOGY.
77
reason the jar of any blow is greatly lessened by the same
cause.
  169.  Use of the Ribs.—Again we  see  the bones of  the
thorax arranged  for  the protection of the enclosed organs.
Within  this  cavity are organs delicate and easily destroyed,
but which require elastic and movable walls.  The elasticity
is easily gained by the cartilaginous portion of the ribs at-
tached to the sternum, which  yields considerably upon pres-
sure ; and  the motion and consequent enlargement is effected
by the oblique position of  the  ribs, as they run downwards
and  forwards from their articulation with the vertebrae.   As
the vertebral extremity is the fixed point, of course the eleva-
tion of the sternal end will enlarge the cavity of the thorax
antero-posteriorly.   Another use of the cartilaginous extrem-
ity of the  ribs is to lessen  the chance  of fracture.   The tho-
rax is exposed to  blows and  falls more than many other por-
tions of the body, and therefore more  exposed to  fracture.
For instance, if a  person  suddenly falls to  the  ground, the
head by an instinctive movement is raised,  while the trunk or
extremities receive the force of the shock.   Also the head or
extremities can by  rapid  movements be  suddenly removed
from the contact with missiles, while the body, comparatively
unwieldy,  must meet the blow.
   170.  Use  of  the  Innominata.—The expanded  condition
of the lnnominatum  affords service and protection in different
ways.  A depression, or cup-shaped cavity is thus  made for
giving a firm support to the organs contained in the  abdomen,
as well as  a solid  foundation to  the spinal  column.   It  how-
ever renders especial  service by furnishing a powerful  point
of attachment for  many of  the muscles both above and below.
those which form the walls of the abdomen, and  many of
those which move the extremities.
   171.  Why  there  are  so many  Bones  in the  Spinal
  169. Describe the uses of the ribs, and the reason why they are partly made up of car
tilage. Why do they run obliquely from the points of attachment?  170. Explain why
 the Innominata are so broadly expanded. 
78
HITCHCOCK'S  ANATOMY
Column.—A large number of bones in  the  spinal column is
necessary in order to give flexibility to the body.  "Were the
number considerably less,  the movements of  the  trunk would
be attended with much more difficulty than at present, and be
devoid of  grace.   And  were  the separated vertebras long
bones, they would  be much more easily broken, thereby  en-
dangering the spinal  marrow.   Another  reason for the great
Dumber of these bones, is the necessity of the elastic cartilage
between them, to protect  the brain.  Were  the joints  fewer,
in order to give equal protection to the brain from jars,  this
cartilage  must  of necessity  have been greatly thickened,
thereby weakening the joint, and  injuring it as a central  axis
of support to the whole body, and also increasing the  liabil-
ity to dislocations,  as well as  greatly endangering  life,  by
pressure upon the spinal cord.
   172. Use of the  Clavicle.—The value of  the  clavicle  lies
in keeping the upper extremity in its  proper position, so as
to prevent  the  humerus from  coviing forward  towards  the
middle portion of the body.  By its direct resistance it also
assists in some muscular actions, such as lifting heavy weights
with the hands.
   173. \ecd of two  Bones in  the Fore-Arm.—The use of
two bones in the  fore-arm, as  already mentioned, is to pro-
duce the movements of supination and  pronation.   And since
these movements are of primary  importance, and one  bone
can not answer this end, two are provided.   Again, if one be
fractured, the other will act as a splint  for keeping the broken
one in place, greatly  superior to the artificial splint, because  the
natural splint needs no compression.
   174. Why several Bones in the Carpus.—In the carpus
are found  eight bones, and  yet we know there  is  but little
motion between them.  The reason why  exactly  this number

  171. What is the reason why so many bones are placed  in the spinal column?  What
is the use of the intervertebral substance? 172. What service does the clavicle render
to the upper extremities?  173. Why are there two bonas in the fore-arm? 174.  Whal
can be said of the many bones of the carpus? 
AND PHYSIOLOGY.
79
is required,  is not so easily explained, but it is evident that
one bone could not perform their function, nor the prolonga-
tion of the radius and ulna to the metacarpus.  Several bones
are required in order to give easy and graceful motion to the
wrist, as well as strength.   One bone  could not answer the
purpose, since the very many offices, which  the  hand has  to
perform, could not  be  effected, unless  the wrist  bones were
vary strongly bound together, and flexible to a certain extent.
The arrangement of the  bones  in  two  rows allows a little
movement of the hand upon the wrist.
   175. Function of Metacarpus—The metacarpus of five
long bones gives support to the fingers.  They are long rather
than short bones, in order to give  slenderness to the hand,
and also to  afford a solid  surface for the fingers  to meet in
the act of prehension.
   176. Need of three Phalanges to the Fingers,  and two
Phalanges  to  the Thumb.—The phalanges  of each finger are
three  in  number, whilst  those  of  the  thumb are  but  two.
The obvious reason  of this is to give greater firmness to the
thumb, and flexibility to the fingers.   The hand  in man dif-
fers from the anterior extremity of all  other animals in the
power of perfectly opposing the thumb to each of the fingers,
which of course gives him a great  superiority in all delicate
manipulations,  and  especially  in  grasping minute objects.
And it is easy to see that  a third phalanx in the thumb would
not only diminish  the  firmness of this member, but would
render the  hand an awkward and clumsy organ, instead of an
 instrument beautifully  and perfectly adapted to  the multi-
 farious offices which it has to perform.
   177.  The  great  Length of the  lower Extremities.  Pe-
 culiarities of the  Femur.—The value of the great length in
 the lower extremities, is  manifest as a means of rapid pro-

  Why would not one bono be sufficient?  175. The use of the metacarpus.  176. Why
 are there but two phalanges in the thumb and three in each finger?  What W!=_ld be
 the effect of a third phalanx in the thumb? 177. Why are the lower extremities pro-
 portionally longer than the  upper ? 
80
HITCHCOCK'S  ANATOMY
gression, and  also  for  affording a firm support  to the trunk
when engaged in the various kinds of labor.   Were these ex-
tremities much shorter  than they now are,  walking would not
only be a tediously slow process, but a laborious one.   The
femur has some remarkable peculiarities.   In the first place
it presents in its articulation with the innominatum  the most
perfect  specimen  of a ball and  socket joint in the  system.
Besides this it bends at nearly a right angle  at its upper  end,,
making what is  called  the neck, and here it is that  the frac-
ture of the thigh-bone generally  occurs.   The  use of this
curvature is to place the points  of support for  the  trunk as
far as possible from the center of gravity of the body, thereby
giving the body the mot  secure position on the lower  ex-
tremities,  and  especially  for  the  attachment  of   powerful
muscles to move the thigh and  leg, as Avell as  to   maintain
securely the trunk when the legs are the fixed points.  This
projection is called the  Trochanter process,  and is spongy or
cellular in its  structure.  And it is not a little interesting to
notice, when this process is sawn through  in a perpendicular
direction,  that the cells are arranged in an arched form from
below  upwards,  thereby greatly aiding the  strength of the
bone.   The same arrangement is seen in some other  bones of
the body,  when they are in an exposed  position.   The lower
extremity  of  this  bone,  as has  already  been mentioned, is
greatly expanded, in the shape of two condyles  for  the  firm
articulation with the tibia.   The  necessity for this lies in the
fact that the knee-joint is one of the most  exposed  joints in
the whole body, and the one which receives the hardest strain.
The protection of the nerves and  blood vessels, which are' sent
to the leg, is also worthy of a  notice.   It  is  effected  by \
deep groove between  the  condyles  on the  backside of  tla
leg, which guards these vessels  from  blows  in  every direc-
tion except behind, from whence they are the  least apt to come.

  What remarkable joint between the femur and the innominata?  What is the ar-
rangement of tho cellular structure in the upper part of the femur? Why has the fe-
mur so li»'-ge processes on its lwwer extremity ? 
AND  PHYSIOLOGY.
81
  178.  Use of  the  Tarsus.—In the Tarsus we see the value
of several bones instead of one.   It is the movement  of these
upon one another that imparts elasticity to the step and firm-
ness of  support to the whole body; and hence  it is  that all
artificial legs produce a limping motion in the  body.    By no
mechanical contrivance can the suppleness of  the tarsus and
of the muscular actions be supplied.
  179.  Two  Bones  in  the  Great  Toe,  and  three  Boms
l n  all  the  Others .—The great toe of the foot, like the thumb
of the hand, has only two phalanges.   This is  mainly for the
purpose of securing greater strength to the foot in walking
and standing.    It is also of service for opposition to the other
toes, as is seen in those rare cases of persons  deprived of their
upper extremities, who can readily make use of the  foot for
many of the  delicate purposes to which the  hand is  adapted,
such as writing, using scissors, and  placing  the crystal  in a
watch.   The  remaining toes, like four of the fingers, receive
a tendon only at the  base of the  second and third phalanx,
the  first one  being  interposed merely to  give  strength  and
slenderness  to the  extremities, as well as  the  power of  sur-
rounding objects in the act of prehension.   The  slenderness
of the fingers above the toes is a distinguishing characteristic
of man, showing that  the office of the foot is merely to  sup-
port the body on the ground, and of the hand to perform the
business of every-day life in its ten thousand  forms.


             HYGIENIC  INFERENCES.

  180.—1.  Reason  of  Distorted Bones.—In the early life
of man  and other   vertebrate  animals,  the animal portion of
bones greatly predominates  over the earthy  constituents, and
hence they  yield more  readily  to pressure, but are  not so

  17S. How do the bones of the Tarsus  give elasticity to the step?  179. How do the
phalanges of the foot compare with those of the hand in number ? Why are the bones of
the hand longer than those of the foot?  180. What kind of matter predominates iu the
early life of bones ? 
82
HITCHCOCK'S  A N A T O M Y
liable to break as in  older  persons.   This is the reason why
falls and blows so seldom do much injury to children.  It is
also the reason why distortions and curvatures of some of the
bones are so common,  since too often children are either urged
or permitted to use their limbs excessively before their bones
are  made  solid by the  deposition of  earthy matter.  These
distortions are most common in children who are weak anr
sickly, because in them the recuperative powers are small.
   181.—2.  Danger  of  Constrained  and  Unnatural  Pos\
tions  in  Children.—Hence we infer that children  should
not be confined in any unnatural or constrained position, but
allowed to move freely in whatever direction nature  may de-
mand.  And all punishments of this sort, inflicted by parents,
guardians, and school teachers upon  young persons, such  as
standing on one leg, or holding a book with an extended arm
for a long time, are  dangerous  and ought to be proscribed,
since they are too often the cause of bow legs  and curvature
of the spinal column.
   182.—3. Cause of the  Rickets.—The  disease known  as
Rickets is produced by imperfect nutrition of the bones.  This
is generally,  though not  always, the result of poverty or vice,
or both  combined.  The direct cause of the disease is a de-
ficiency of earthy matter in the bones.   This is either ab-
sorbed or never produced, and as a result the bone is softened,
and by the tonicity of the muscles the  body is drawn  into un-
sightly deformity.   An  observance of the  laws of  health  is
the best medicine for this disease.
   183.—4. Need  of Cleanliness of the Teeth—Tooth Pow-
ders—Tooth Picks—Decayed  Teeth —Worthless   Teeth
! !iouId be Extracted.—From the almost inevitable exposure
of the teeth to mechanical and  chemical agen's, we  see that
they need considerable care and  attention.   They need to  be
 Why do falls and blows seldom injure children as they do adults? In what children
are distortions the most common ?  181. Why should children be unconstrained in their
bodily exercise ?  What is said about punishments that distort the bones of children?
182. What is the usual cause of Rickets?  What is the best medicine for it?  183. Give
the most important hygienic rule for the preservation »f the teeth, 
AND  PHYSIOLOGY.
S3
kept clean.  This can ordinarily be accomplished  by the use
of a soft tooth brush and  pure water thoroughly applied at
least once in the twenty-four hours.  A tooth-powder of an
alkaline character, or, what is the same thing,  clean toilet
soap,  can  be occasionally used with benefit.   A tooth pick
should be possessed and  used  by every gentleman and lady
too, though  it should  be made of wood, ivory, tortoise-shell,
bone, quill, or some substance softer than the tooth itself.  If
the teeth are very closely set  together, frequently drawing a
thread between them will aid in preventing decay.   If any of
them have begun  to decay, a good dentist should be consulted
as soon as  possible, and the  cavities filled with gold, since ar-
tificial  teeth  can never  be  so  valuable  as natural ones, even
though partly  filled with  gold.   When  teeth  are  past  filling
they should  be removed,  as  they are the means of producing
decay in others, a3 well as many pains called neuralgia.
   184.—5.  The  Teeth  not to be  Used on very Hard Sub-
stances.—The teeth should be used only for the purposes for
which  they were designed.  The teeth of squirrels, rats, and
beavers were made expressly for cutting wood  and gnawing
open nuts,  but not so with the  human teeth.   Even the con-
stant biting of thread,  the holding of a  pencil or tobacco-pipe
between the teeth, and especially  the  cracking of nuts, are
practices very injurious,  and often  cause the  decay of these
organs.
   185.—6.  Teeth  Generally  Decay  Early  in  Life.—Ex-
perience shows that teeth decay the most rapidly in the early
part of life, generally  between the   ages   of  fifteen  and
thirty.   Hence youth  need  to  take  especial care  to preserve
them,  not  only on account  of  the pain and  deformity which
t.ieir loss occasions, but because of their remote  effects upon
the voice and especially upon the digestive organs.

  What kind of tooth powder is the best? Who should use tooth picks? What treat-
ment should be given to decaying  and  decayed teeth?  What substance alone should
teeth be filled with ? 184. For what purposes should human teeth never be used?  1S5.
In what period of life do teeth decay the fastest?  What are important reasons for an
especial care of the teeth ? 
84
Hitchcock's  anatomy
    186.  Classification  of Animals.—The highest and most
 competent authorities differ widely in their attempts to classify
 the Animal Kingdom ;  that is, to divide it into smaller groups,
 which are  Sub-Kingdoms  or Provinces, Classes. Orders, Fa-
 milies,  Genera,  and Species.   We  have no room, had we  the
 ability,  to  decide  these  difficult questions.   There is,  how-
 ever,  a general  acquiescence in  the principle first introduced
 by Cuvier, that animals were  created  on four great types or
 plans, which  he  calls  Vertebrata,  Articulata, Mollusca,  and
 Radiata.   The discrepancy lies chiefly  in  the subdivisions of
 these  leading  groups.   We shall merely present the classifi-
 cations of two of the most eminent living anatomists and zoolo-
 gists—Professor Louis Agassiz of Cambridge, and Sir Richard
 Owen of London—not attempting to decide between them.

   187.  Agassiz divides the whole animal kingdom into four great branches,
 the same  as  those named above.  The Vertebrata he divides into eight
 classes: 1, The Myzontes, subdivided into two orders;  2, Fishes proper,
 into two orders; 3,  Ganoids, into three  orders;  4, Selachians, into three or-
 ders;  5,  Amphibians,  into three orders; 6,  Reptiles, into four orders; 7,
 Birds, into four orders; 8,  Mammalia,  into three  orders.
   The  Branch Articulata he divides into three classes: 1, Worms, with three
 orders;  2, Crustacea, with four orders; 3, Insects, with three orders.
   The  Branch Mollusca  he  divides into three  classes: 1, Acephala, with
 four orders;  2, Gasteropoda,  with three orders;  3, Cephalopoda, with two
 orders.
   The  Branch Radiata ho divides  into three classes: 1, Polypi, with two
 orders;  2, Acalephae, with three orders;  3 Echinoderms, with four orders.
   188.  Owen calls the above-named four divisions of the Animal Kingdom,
 Provinces. Tlu Province Vertebrata he subdivides into four classes: 1, Mam-
 malia, with fifteen orders;  2, Aves, or Birds; 3,  Reptilia, with fifteen orders;
 4,  Fishes, with eleven orders.  His fifteen orders of Mammalia are: 1, Mono-
 tremata; 2,  Marsupialia;  3, Rodentia;  4,  Insectivora; 5,  Cheiroptera;  6,
 Bruta;  7, Cetacea;  8, Sirenia;  9, Toxodontia;  10, Proboscidea; 11,  Peris-
 sodactyla; 12, Artiodactyla;  13, Carnivora; 14,  Quadrumana; 15, Bimana.
  The  Province Articulata he divides into six  classes:  1, Arachnida, with
 four orders; 2, Insects, with eleven orders; 3, Crustacea, with eleven orders;
4,  Epizoa, with three  orders;  5, Anellata, with four orders; 6 Cirripedia,
 with three orders.
  The Mollusca he divides into six classes: 1, Cephalopoda, with two orders.-
2,  Gasteropoda, with ten orders;  3, Pteropoda, with two orders; 4, Lamelli-
branchiata, with two orders ; 5, Brachiopoda ;  6, Tunicata, with two orders. 
AN!* PHYSIOLOGY.
85
  The Radiata he divides into nine classes:  1, Echinodermata ,•  2, Bryozoa;
3, Anthozoa;  4, Acalephae; 5, Hydrozoa; 6, Coelelmintha;  7, Sterelmintha;
8, Rotifera; 9, Polygastria.
  189. To the above Animal Kingdom Pro£ Owen has added another kingdom ol
organisms, " mostly of minute size, and retaining the form of nucleated cells,
which manifest the common organic characters, but without the distinctive
euperadditions of true plants or animals." These he calls Protozoa, and ar
ranges in three classes: 1, The Amorphozoa, or Sponges; 2, the Rhizopoda,
which are the Polythalamia, or Foraminifera;  3, the Infusoria, or Animalcula
/-the last two classes being mostly microscopic.
            COMPARATIVE  OSTEOLOGY.

   191. Microscopic Structure.—In microscopic structure and
cemical composition the bones of  mammals,  including man,
and of  all vertebrates  are essentially tho same, and in  their
general outline a considerable degree of correspondence  can
be traced between many of  the bones of the  human  system,
and those performing similar functions in the  lower animals.
Thus we  almost always find  the femur to have a globular
head on its upper extremity supported by a neck which makes
a considerable angle with the  shaft, and the  two large  con-
dyles on the lower extremity.

   192.  Spinal  Column of Mammals.  Cervical. Dorsal,
Lumbar, Sacral, Caudal Vertebrae.—In Mammals the Spinal
Column is made up  of  five classes of  vertebrae :  the cervical,
of the neck ; the dorsal, of the back;  the lumbar, of the loins;
the sacral, of the hip;  and the caudal, of the tail.  The Cervi-
cal vertebrae, with but two or three exceptions  in all mammals,
consists of seven in number.   The average number of the  Dor-
Bal is thirteen, the Bats having eleven,  and one of the Sloths

 191. What is the microscopic structure of the bones of Mammals? What about the
general correspondence in outline, etc. ?  Instance the femur.  192. What are the fiva
classes of Vertebrse ? How constant is the typical number seven for the Cervical ver-
tebra? ?  Give the average number of the Dorsal. 
86
HITCHCOCK'S   ANATOMY
Fig. 95.
  Skeleton of the Camel.  ■». c. Cervical Vertebrae,  v. d. Dorsal Vertebrae,  v. I. Lum.
bar Vertebrae,  v. s.  Sacral Vertebrae.  v. q. Caudal Vertebrae,   o.  Scapula,  h. Hume.
rus.  c. Ribs.  cu. I'lna.  ca. Carpus,  m. c. Metacarpus,  ph. Phalanges, fe. Femur,
ro. Patella, ti. Tibia,  ta. Tarsus,  m, t. Metatarsus,  cl. Clavicle.
                         FiG. 96.

7TVC
Skeleton of Bat.  The descriptive letters are the same as in Fig. 95.
twenty-three.    The  Lumbar are usually the  largest  in  size
and  their  range  is from  two  to  nine.    The  Sacral  consist 
AND   PHYSIOLOGY.
87
usually of four, but vary from one to nine, and as in  man,
are almost  always  consolidated.   The  Caudal vary exceed-
ingly in number, sometimes amounting  to forty-six.   When
of this number, they gradually dwindle away towards  the ex-
tremity of  the tail, and lose the  characteristics  of  vertebrae
and become mere ossicles or bits of bone.
   193.  On  what  Length of Neck depends.—Hence  we see
(hat the length of the neck in quadrupeds does  not  depend
on the number, but on the length of vertebrae, since the Cam-
eleopard (Fig.  97),
iw                     •s
  Skeleton of Cameleopard.  C. Cervical Vertebrae. D. Dorsal Vertebrae.  /.. Liimbar
Vertebrae.  8 Sacral Vertebrae,  cd. Caudal Vertebrae.  51. Scapula.  53. Humerus.
64 Ulnft. 55. Pvadius. 56. Carpal Bones. 5T. Metacarpus. Hi. and in. Phalanges. 62. Inno-
min.tum. 64 and 65. Femur. 66'. Patella. 66. Tibia.  67 and 68. Tarsus. 69. Metatiriu* 
88            HITCHCOCK'S  ANATOMT

which has the longest neck,  has only seven cervical vertebras,
the same number with the Mole (Fig. 98), an  animal with

                          Fig. 98.
Skeleton of the Mole.  The illustrative Figures represent the same as in Fig. 97.
one of the shortest necks  among quadrupeds.   Cuvier states
that in general the length of the neck is such, that, added to
the head, the length of both is equal to the height of the ani-
mal's shoulders above the ground.   If this were not the case,
grazing animals could not reach their  food, nor any quadru-
peds their drink without bending the legs.

   194.  Shape of Body.—The shape of the body of quadru-
peds, whether slender, or  short and thick, depends  on the
number and size of the Lumbar  and Dorsal vertebrae.
   195.  Bones of Skull.  Elephant's  Head.   Styloid, and
Tympanic Bones.—The general arrangement  of the bones
of the skull, as well as their number, corresponds very nearly
with  those  of man.  The  two  Parietals are  usually small
bones, and sometimes united into one.   This is true of the
Horse and  the Bats.   In the  Hog and Rhinoceros  the two'
parietal bones are united  in  one, while  their frontal bone  is;

 What peculiarity about Lumbar?  What of the Sacral? How largo a number of Sa-
cral are sometimes found ? 193. Upon what does the length of neck in quadrupeds de-
pend on ? Instance the Giraffe and Mole. What is the general rule about the length of
the neck ?  194. What does the shape of the body mainly depend on? 195. How  i*
the Parietals sometimes differ from man ? 
AND  PHYSIOLOGY.
89
Fig. 99.
t       f  o    n    m
                    mi            mo     c
   Skull of Horse,  oc, t., f.  Occipital, Temporal, and Frontal Bones,  n., m., im.
  and mi., Nasal, Superior Maxillary, Intermaxillary, and Mandibular Bones, o. Orbit.
  i. Incisive Teeth,  mo. Molar Teeth.

in two  pieces.   In nearly all the  orders  of mammalia this
bone  (the  frontal)  is always found in two  pieces.  In  the
Elephant the bones of the  cranium are all  united into one
at an early period in life, forming but one piece, in  order
probably to make  it  sufficiently strong to support the great
weight  which  is  brought  upon  these bones  by  the  tusks
and proboscis.    The Styloid process  of  the temporal bone
is usually in  mammals a separate ossicle.   The bone  which
contains  the  organ  of  hearing  in  all  mammals,  except
man  and the Apes, is a  separate bone called the Tympanic,
and is  not simply the petrous portion of  the temporal as in
man.

   196.  Bones  of  Face,  l.ikruiuxillanes, Lower Jaw.—
In  the  Face too the bones correspond very nearly with those
in man.  The essential difference is found in the upper jaw.
Instead of the two superior maxillaries meeting each other on
the median line of the body in front, there  are two other bones
between them calted the  Intermaxillaries.   These are very
conspicuous in  animals provided with  large canine teeth, or
tusks, as  the  Elephant  and Squirrel.  The Lower Jaw in

  What peculiarity about the  bones of the Elephant's skull ? What bone Is wanting in
the Whale ?  Describe the Tympanic Bone. 196. In what respect do the bones of the
face in Mammals differ from those in man ?  Where are the  Intermaxillaries ? 
90
HITCHCOCK'S  ANATOMY
quadrupeds generally consists of two pieces, the division being
made on the median  line of the body.   In  the Hog, Horse
and  Cow it consists of a  single  bone.    In the  Greenland
Whale it is  in its simplest form, which is that of two arched
ribs.

  197.  Form  of  Skull, of Orang 0 ut a ngs.—Viewed  as a
whole the form of the skull departs most from that of man in
the lowest orders.   In  the  Ornithorynchus the  face  is pix>
longed  into a beak or bill,  and in  the Horse the facial por~
tion of  the head is four times larger than the cranial, exactly
the reverse of the  case in man.  In the young Orang  Outangs
the form of the skull  very closely resembles that of man, and
in the adult  the size of the exterior  of the cranium nearly
equals that of man, though  its capacity is considerably less.

  198.  Teeth  of  Quadrupeds, Carnivorous,  Herbivorous,
Insectivorous  and Barbed Teeth.—The Teeth  of Mammals
vary exceedingly.  They may, however, be classed under the two
divisions of flesh  and vegetable eating, according to the food
of the animal.  Those made  to  live on  meat  are  sharp and
                           pointed, for simply tearing the flesh
          Fig. 100.           into such  small  portions  that it
                           can be  swallowed, while those eat-
                           ing herbs and grass, have the front
                           teeth with sharp edges like that
                           of  a  knife for  cropping the food,
                           and back  teeth with flat surfaces,
                           or  vertical ridges of enamel  in-
                           terspersed between  the ivory  or
                           dentine,  which  act   the   same
                           part when brought together with
Teeth ofaLion (Carnivorous Animal )a  lateral motion, as do  tile Upper

  What of the Lower Jaw? 197. In what orders does the head differ most from that of
man? How does the skull of  the Orang Outang differ from that of man': 198. What
are the two kinds of teeth among mammals? Describe each. Give the ie_sou why tha
teeth are furnished as they are.
 
AND   PHYSIOLOGY.
91
Fig. 101.                    Fig. 102.
Teeth of an Herbivorous Animal.        Teeth of an Insectivorous Animal.
and nether millstone  for  grinding grain.   Those  which  live
upon small insects have conical teeth with corresponding de-
pressions in the opposite jaw in order to crush the  skeletons
and envelops of their prey.   The Seals, which  live on Fish,
are provided w7ith barblike appendages similar to those on fish-
hooks, in order that they may hold their slippery  prey.

   199. Humerus, in Burrowing  Animals.—The Humerus
is generally a long cylindrical  tube, with  a large  rounded
head at its upper extremity.   But in swimming and burrow-
in cr animals it  is a short and curved bone, with each extrem-
ity very much modified for the  attachment of muscles, since
the fore-legs  of such animals need to be  used with  great fre-
quency and force.

   200.  Bones of  Fore-Arm.   Carpus, Metacarpus, Pha-
langes.—The element in which  mammals live,  greatly modi-
fies the bones of the fore-arm and hand.   (Fig.  103, p.  92.)
In general there are two bones in the fore-arm, and but few
animals have  the power to move these one upon  another like
man.  The Carpus is constantly  made up of two rows, though
not of the same number.   They vary from five to eleven.  Tl©
Metacarpus consists of five elongated bones for the most part.'
But these  are three  in  the  Rhinoceros, and  one  with two

  What is remarkable about the teeth of the Seal ? 199. What is the general outline ol
the Humerus ?  In what animals is it modified ?  200. What effect has the element, in
which animals live, upon the anterior extremities ? How do the Carpal Bones range iq
number? What are the exceptions to the typical number five of the Metacarpus? 
92
hitchcock's   a x a t (> m y

             Fig. 103.
    B        C          J)      E
  Anterior Members of different Animals.  A. Fish.  B. Bird.  C. Dolphin. D. Deer.
E. Bat.  F. Man.

rudimentary bones in the Horse.   From one to five fingers are
usually found, of which the thumb is generally  rudimentary,

             Fig. 104.                          Fig.  105.
  Hind Foot of Horse,  t. Tibia,  ta. and       Foot of Stag.  (Representative let-
ta'. Tarsus,  c. Metatarsus or Canon Bone.     ters the same as in the last figure.)
«. Rudimentary  Bone,  p., pi., and pt.,
first, second and third Phalanges. 
                    ANDPHYSIOLOGY.                93

consisting only of a single bone.   The Elephant has five toes,
the Hog four, the Rhinoceros three, the Cow  two. and  the
Horse one.   Sometimes the longest finger  (paddle)  of  the
Whale contains eleven bones.   In burrowing and swimming
animals the fore-feec are generally the largest, and among some
quadrupeds the reverse is the case.  The posterior extremities
of quadrupeds are usually less modified than the anterior ones,
a_ they are used mainly for support and progression.


               OSTEOLOGY  OF  BIRDS.

   201. Vertebrae,  Cervical,  Dorsal, Caudal.—Birds  exhibit
several peculiarities in their Spinal Column.   The number
of Cervical  Vertebrae is much  greater  than in mammals,
giving them long  and flexible necks.   (Fig.  106, p. 94.)
The  number is between ten and fifteen, but the  white Swan
has twenty-three.   The  Dorsal  Vertebrae  vary in number
from  seven  to nine, and admit  of  but  little  motion upon
each  other,  many of  them being frequently  anchylosed to-
gether, as in  the  human sacrum.   (Fig. 107, p. 95.)  The
design of this  is to give the firmest point  of attachment to
wings that can be secured.   The Caudal Vertebrae are hol-
low and  form a complete canal  for the spinal marrow.  The
last one  has  a large disc-shaped  process upon it for the sup-
port of the long feathers of the tail.

   202.   Bones  of Head, Os  Quadratum,  Jugal  Bone,—
The   bones  of the head  correspond  in number  and position
for the most part  with those of  the mammalia.  (Fig. 108,
p. 95.)   They are, however, united  together  at a very early
period, and the sutures can not  be recognized except in very
young subjects.   One point of difference between these skulls

  What are some modifications of Phalanges?  201. Compare the Cervical Vertebrae ol
Mammals with those of Birds.  What number of Cervical Vertebrae has the Swan? Why
are the Dorsal Vertebrae usually firmly fixed together ?  What peculiarity of the Caudal
Vertebras ?  202. What can be said of the Sutures in the head of birds ? 
u
hitchcock's   anatomy
                Fig.  106.
D. I). Dorsal Vertebra?.  S.  S. Sacral
52. Coracoid Bone.   53. Humerus.  54
  Skeleton of Swan.   C. C. Cervical Vertebrae.
Vertebra},  cd. Caudal Vertebne.  51.  Scapula.
and 55. Radius and Ulna.  56. Carpus.  57. Metacarpus.  53. Furcula.  62. Innominata.
03. Sacrum.  64.  Pubis.  65. Femur.  e6. Tibia.  65'.  Patella.   67. Fibula.   69. Tarsa
Metatarsus,  t., *'*., Hi., iv. Phalanges. 
AND   PHYSIOLOGY.
»S
Fig.  107.
Sacrum. Scapula. Humerus.
Cervical Vertebne.
Coccyx.
Tibia.
Phalange.
 Clavicle or Furcula.

. Sternum.
Tarsus.
Skeleton of the Goeland.
and those of  the  mammals is  that  the occipital bone  con-
sists of four parts  instead of one.   A small bone, too, is  al-
ways  present  called the Os Quadratum,  in close proximity
with the occipital,  temporal, and maxillary bones.   A Jugal
Fig. 108.
  Orbit.  Inter-Orbitar Septum.
       Lachrymal Bone.
         Nostril.
Sup. Maxil- v    \
Cranium.
                                Tympanum.

                             ^ Os Quadratum.

Nasal Fossre.' Jugal Bone. Infer. Maxil.
        Head of the Eagle.
What bone in the skull of birds that demands attention?
                    5 
96
HITCHCOCK'S  ANATOMY
Bone is also found which is  similar in position to the zygo-
matic process of the temporal bone in man.

   203. Bill.—Teeth  are  entirely wanting in  Birds, their
place being supplied by a single horny projection on each jaw
known as the Bill.  Teeth are not needed by  these animals,
since mastication,  where it is necessary that it should be per-
fcrmed, is done by the gizzard.

   204. Ribs.—The Ribs are very  firmly articulated with the
sternum by bone and not cartilage, so that  they have a ten-
dency to  keep  the thorax  as  fully distended as possible all
the time,  which is its natural position.
Fig. 109.
                                   205.   Sternum,  in  what
                                 Birds  largest.—The  Ster-
                                 num is the  most  striking of
                                 all the  bones  in a bird.   It
                                 is the  largest bone in their
                                 bodies, a flattened  and  some-
                                 times quadrangular bone, hav-
                                 ing  upon its anterior surface
                                 a prominent  ridge  like  the
                                 keel of a ship, for  the attach-
                                 ment of the  pectoral muscles
                                 used  in  flight.   The size of
                                 this ridge generally stands in
                                 direct relation  to the powers
                                 of rapid  flight, and  hence in
the Humming  Bird, one  of the swiftest  on  the wing, it is
proportionally the largest.
   206. Clavicles,  Coracoid  Bone.—The  Clavicles  cf  birds
present a marked peculiarity.   They both unite  at their  an-
terior extremity, forming  a  forked bone known  as the Fur-
  Bones of Sternum and  Shoulder of
Birds.  «. The Sternum,  e. Notch of the
Sternum,  co. Origin of the Sternal Ribs.
6. Crest. / Fourchctte. c. Coracoid Cla-
vicle, o. Scapula.
 203. What serves the purpose if teeth for Birds ?  204. How does the articulation of
the ribs affect the condition  of the chest?  205. Which is the largest bone in birds?
How may we know the powers of flight in a bird by the keel of the Sternum ? 206. Whaf
do the clavicles of birds form as they are united together? 
AND  PHYSIOLOGY.
97
cula, merry thought, or wish bone.  They also possess another
bone which acts  the  part of a clavicle,  called the  Coracoid.
It reaches  from the scapula to the sternum,  side by side with
the Furcula,  and  is  a  principal source  of support  to the
wings  in  flight.   There  is a  bone  analogous to this among
some reptiles.
   207. Humerus.—The  Humerus is generally  a  larger and
Stouter bone than the femur, contrary to the relative propor-
tion in man.  This is because  the anterior extremities of birds
are of much more importance in their habits than the poste-
rior ones, since the hind  legs  in most of the flying birds act
merely as  a support for the body when at rest, and are not of
special service for running or scratching.
   208. Bones  of  Wings, Fingers.—The two  bones  of the
fore-arm  are proportionally longer than  the  same  bones in
mammals, and are longest in birds of flight.   The carpus is
represented by two  short bones, and the metacarpus is of the
same number.  In some birds the thumb is  entirely wanting,
but when  present  it  is  made up of  two bones.   The  little
finger has only one bone.   The middle  finger is the longest,
consisting of two and even three bones.
   209.  Femur,  Tarso-Metatarsus.—The Femur  is  both
thicker and shorter than the bones below it, which constitute
the leg.   The Fibula is always, partially at  least, united with
the tibia at its  lower extremity.   The Tarsal and  Metatarsal
Bones are found as  one, called the Tarso-Metatarsus,  which
has at  its lower extremity three pully-shaped heads  for the
attachment of the toes.

    210. Sesamoid Bones.—Sesamoid Bones are abundant in
 Birds,  and in many cases even the tendons themselves  become

   Is this peculiar to birds alone ?  207. What is the comparative length and size of the
 Humerus and Femur in birds? Why are the anterior  extremities in most cases trio
 longest?  208. What is said of the two bones of the fore-arm?  How many bones are
 there in  the  Carpus? Describe the finsrers of birds. 209. What peculiarities in the
 lower extremities of birds? Describe the Tarso Metatarsal Bone.  210. What la saiti
 about Sesamoid Bones in birds? 
98            HITCHCOCK'S  A X A T O M Y

considerably ossified.    This is especially  true of  those in
the leg.
  211.  Birds Bones are hollow.—The bones  of birds are
more or  less hollow internally, devoid  of marrow, and  per-
meated by air.    Hence  they are provided with openings con-
nected with the respiratory apparatus through which the air is
brought into them. As a general rule the capacity  and cxtei.t
of these openings throughout the skeleton depends  on  the size
of the bird, and its powers of flight, since  small though rap-
idly flying birds have few hollow bones;  in larger and higher
flying species, however,  they are numerous.    In  the Apteryx
of New Zealand there  is the greatest want of these cells. This
bird has no wings,  but can  run and even burrow in the earth
very rapidly.   Those  bones  which convey the air, eiffer from
all  others  in appearance by their whiteness and more com-
pactly cancellated or cellular structure.


              OSTEOLOGY  OF  REPTILES.

  212.  Number  of Vertebrae  in Reptiles.—The  Vertebrae
of Reptiles vary  exceedingly  in  number.   '-For  whilst  in
the tailless Batrachia only nine or eight cervical  vertebrae are
counted, some serpents  have full 300."  Those of Batrach-
ians have long transverse processes.

  213. Ribs;  Use of  Ribs  to Serpents.—" In the serpents
the ribs are  both  very numerous and very  movable; where
they cease the tail begins; here the Caudal vertebras  may be
distinguished from the other vertebras of the trunk, whilst ad
distinction of dorsal and lumbar vertebras fails."'   They are
 211. Why are birds' bones usually hollow and more or less occupied by cavities?
212. What is the number of vertebrae in Reptiles?  213. Give the number of ribs in
Reptiles.  How do they differ from those of quadrupeds ?  Of what service are they to
the animal ? 
AND  PHYSIOLOGY.
99
valuable  instruments of progression,  since  in manj?  they can
be placed upon the ground and used as feet.

   214.   Shell  of  Tortoise,—In the Tortoise  that portio*
which is  commonly called the shell,  is made  up  of the C_nr

                            Fig. 110.
                     P                       f

  Skeleton of the Tortoise; the Plastron has been removed,  vc. Cervical Vertebrni
•cd. Dorsal Vertebra', c. Ribs.  cs. Sternal Kibs.—The Marginal Bones of the Cara.
pace: o. Scapula,  cl. Collar Bone.   co. Coracoid Bone.  b. Pelvis.  / The Femur.
t. Tibia, p. Fibula.


pace or upper portion, and the Plastron, or lower one.    The

Carapace seems to be a mere expansion  of the vertebras, and

the Plastron an expanded  sternum.   Hence, as the  annexed

  214. What is the Carapace and what is the Plastron in the Turtlo family? From what
bones are they developed? 
100
HITCHCOCK'S  ANATOMY
cut shows, the skeleton of the Tortoise is  a very simple one,
and  the skeleton  of  the  Frog, as  shown  in  Fig.  Ill, is
equally simple.
   215.  Humerus.—The  Humerus  of the Tortoise is  short
and very much curved.  This is made so in order that the
animal may thrust its  extremities out  of the shell and  reach
the ground, which  could  not be done if  the  humerus  weie
straight as it is in most of the other vertebrate  animals.
   216.  Femur.—The Femur is curved in  the same animals
for the same reason.

   217.  Phalanges.—Frogs generally  have four fingers, with
from  two to four phalanges  in each finger.   Tortoises and
Lizards generally  have  five  fingers,  and  from  two to five
phalanges in each finger.

                          Fig. 111.
Skeleton of the Frog.
              OSTEOLOGY  OF  FISHES.


  218.  Bony  and  Cartilaginous Fishes.—The skeletons of
Fishes are of  two kinds, those  made up of bony, and those of
cartilaginous matter.  (Fig. 112.)  The microscopic structure
of the scale of  a Pike is seen in Fig.  113.   Of the former kind

  215. Why is the  Humerus of the Tortoise curved?  217. How many fingers  have
Frogs, Lizards, and Tortoises? 218. What are the two kinds of skeletons in Fishes I
Give examples of each. 
AND  PHYSIOLOGY.
101
as  representatives  are   the              Fl»- 112-
Shad and Flounder,  and  of
the  latter,  the  Shark  and
Sturgeon.
   219.  Two  Kinds  of  Ver-
tebra.—The  only  kinds  of
Vertebras in  Fishes  are the
Dorsal  and Caudal.   These
vary  in number from seven-
teen to  more than a hundred.
Their bodies (vertebras) pre-
sent on both articulating sur-
faces a conical depression which
is filled  with  a  soft  matter
having the  same use as  the
elastic   intervertebral   sub-
stance in the human vertebral
column.
   220. No  Sternum  or Pel-
vis.—The Sternum and Pel-
vis are both wanting in fishes,
and the anterior and posterior
extremities  are rudimentary,          skeleton of the Perch.
being represented by fins.
                            Fig. 113.
 Section of the bony scale of Lepidostms. a. Showing the regular distribution of the
Lacunae and of the connecting Canaliculi.  b. Small portion more highly magnified.

 219. What are the only Vertebrae of Fishes?  What is peculiar about their articmia-
ting surfaces?  220. Why have Fishes no Sternum or Pelvis? 
102            HITCHCOCK'S  ANATOMY

   221. Head.—The bones of the Head in this class of  ani-
mals  are  numerous  and  exceedingly  complicated,  being  in
fact a difficult portion of study in comparative osteology.   It
is, however, a subject of great  interest to a thorough scholar
of this branch of anatomy ; but as so little of it  can be gen •
eralized, it must be omitted h re altogether.
   222.  Great Variety of Teeth.—The  Teeth present  every
yjssible  variety in position  and  size, and,  as Sir Richard
Owen says, "they average  in  number from zero  to  count-

                            Fig. 114
                         t_    or
                                      :j>io
    Head of the Pike.  c. Cranium,  n. Nasal Fossae,  im. Intermaxlliary Bone.
  m. Upper Jaw. p., op., to. Bones peculiar to the head of fishes.

less quantities."    Some  teeth,  in  shape  and lo_&,cion re-
semble the pavement of  the street,  others  are of a  delicate
hook-shape,  and others still  are fine as hairs, and are located

                           Fig. 115.
Head of a Shark.
 221. What is remarkable with respect to the bones of the Head in this class? 222. Whal
is said about the variety of Fishes' Teeth?  How numerous are thor round at times? 
AND  PHYSIOLOGY.
103
on  the jaws, tongue, and palate.   They are repeatedly re-
newed during the  life  of the animal.   Fig.  116 represents
the microscopic structure of the tooth of an Eagle Ray.
                          Fig. 116.
Microscopic structure of Tooth of Eagle Bay.
  223.  Skeleton,  or Harder  Parts of Invertebrata—The
harder parts of invertebrate animals generally differ so much
from bones in composition and structure  that the term Osteo-
logy may perhaps  be less  proper  than  that  of Skeleton in
describing them.

  224.  Skeletons  of  Crustaceans.—Among the Articu-
lata the Crustaceans have a more or less solid external crust
of carbonate of lime  in a base of peculiar azotic matter, in-
soluble in caustic potash, called  Chitine.

  225.  Skeletons of Insects.—Insects, the most numerous
class of articulated animals, have a  chitinous covering, gener-
ally leathery, but sometimes solid.   The Arachnoidea have a
similar skin, soft or coriaceous, rarely horny; and the Anne-
lida a very  thin epidermis.    The Helminthes, Rotatoria, and
Turbellaria, reckoned in this  branch of the animal kingdom
 What is curious about their renewal?  224. Describe the skeleton of Crustaceans?
225. What is the skeleton of Insects ?
                              5* 
104            HITCHCOCK'S  ANATOMY.

by some eminent writers, have a skin more or less hard, and
sometimes spinous.
                           Fig. 117.
            Microscopic structure of the Spine of Sea Hedge-Hog.
  226.  Skeleton  of   the  Mollusca. — In all the  three
great classes of Molluscs, the  Acephala,  the Cephalophora,
and the Cephabpoda, the animal possesses a mantle by which
it is  able  to secrete a solid  deposit, mainly composed of car-
bonate of lime, which it spreads over nearly all the body, and
is  fastened  to  it by muscles.  In the  Acephala  this skele-
ton is in two pieces, called valves;  in the Cephalophora, it is
in one piece, except that a calcareous plate is attached to the
foot  to  close  the orifice.   The organic base of  these  shells
sometimes, but rarely, predominates over the calcareous part.
In the Cephalopoda there are cartilages for the attachment of
muscles similar to  the  same substance in vertebrate animals.
In the  Argonauta and Nautilina  of this class,  the mantle
secretes an  external shell;  but in the Loligina, or Cuttle Fish
family,  it is internal.
   The structure of the shells of Molluscs is often  complicated
find beautiful.
   227.  Skeletons  of   the  Radiata.—Among   the Polypi
gome are entirely soft;  others have a solid  skeleton,  which
  226. Describe the skeleton of Molluscs.  227. What are the skeletons of Radiates ?
What is their chemical composition ? 
and  physiology.               105

        Fig. 118.
Microscopic view of Shell of Pinna.
is calcareous, horny,  or leathery.   This skeleton, called a
polypary, or  in  popular  language  coral,  is  secreted  by the
skin of the animal, and  seems to be truly an internal skele-
ton.   It contains, say ninety-five  per  cent,  of carbonate of
lime, some two or three per cent, of fluorides and phosphates,
and  from four to eight per cent, of organic matter.
   The Acalephas, another class  of  Radiates,  are mostly gela-
tinous ;  but a few are cartilaginous, and some have a nuclear
skeleton.  The Echinodermata,  with few exceptions, have an
                           Fig. 119.
Microscopic section of hinge of Mya showing a crystalline structure.
What is coral ? What is the skeleton of other Radiates ? 
106           HITCHCOCK'S  ANATOMY.

external skeleton highly calcareous.  In the Asteroidea there
is also  an internal articulated skeleton.   The structure of
these skeletons is  too  complicated  for description here.  The
Echinidae are remarkable for calcareous knobs and rays, both
sharp and  blunt, sometimes several  inches  long;  hence this
common name, Sea Hedge-Hog, or Porcupine.
   Skeletons  of   the  Protozoa.—The  organisms  brought
together by Prof. Owen under Protozoa, are the Amorphozoa
or Sponges,  the  Foraminifera, and  Infusoria,  "which,"  he
says,  "manifest the common organic characters, but without
the distinctive super-additions  of true plants or animals."  Of
the skeletons of the Infusoria Ave  know little, save that they
occur fossil, and are composed  of silica and iron  ore.
   The Foraminifera are small, gelatinous animals, protected
by a calcareous shell.   The Sponges are  said to be ceratose
or horny, siliceous or flinty, and calcareous or limy, accord-
ing as their frame-work partakes of these several characters.
What if said of the skeletons or the Protozoa?  What of the Forminifera? 
CHAPTER   SECOND.
THE MOVING POWERS  OF THE SYSTEM.—MYOLOGY,  OR  THE
                  HISTORY  OF  THE MUSCLES.
         DEFINITIONS  AND  DESCRIPTIONS.


   228.  Microscopic  Structure  of  Muscle.—The  Muscles,

known  as  flesh  or lean meat,  compose  a large part  of the

extremities,  and  the covering of  the trunk.  To  the naked

eye they appear  to be fibrous, and, with the  assistance  of the

microscope, these fibers  are found to  be bundles—called Fasci-

culi—of still smaller fibers,  called  Ultimate  Fibers.   These

seem  to be  polygonal  in  form,  and with an average diameter

of j^oth of an inch  in man,  though  in some  of the lower ani-

mals their size is much less.

  View  of the stages of development of
Muscular Fiber.  1, A Muscular Fiber of
Animal  life enclosed  in its Sheath or
Myolemma. 2, An Ultimate Fibril of the
same. 3, A more highly magnified View
of Fig. 1, showing the true nature of the
Longitudinal Striae, as well as the mode of
formation  of the Transverse Striae.  The
Myolemma is here so thin as to permit the
Ultimate Fibrils to be seen through it. 4.
A Muscular Fibre of Organic life with two
of its Nuclei; taken from the Urinary Blad-
der, and magnified  600 Diameters. 5, A
Muscular Fibre of Organic  life from the
f miach, magnified the same.
   229.  Fibrils. —The   ulti-

mate  fibers  are  still further divisible into what are  termed

Fibrils.  These  have an average diameter of about roo-ooth
 228. What is lean meat?  How does muscle appear to the naked eye?  What are the
three microscopic elements ?  Describe each.  229. What is the diameter of the Fibrils' 
108             HITCHCOCK'S   ANATOMY
Fig. 121.
  A View of the Fragments of Striped elementary Fibers, showing a cleavage in opposite
directions—magnified 300 Diameters.  1, The Longitudinal Cleavage.  2, The Transverse
Cleavage, the Longitudinal Lines being scarcely visible.  3, Incomplete Fracture,follow-
ing the opposite surfaces of a Disc which stretches across the Interval and retains the two
Fragments in connexion. The Edge and Surface of this Disc are seen to be minutely
granular, the Granules corresponding in size to the thickness of the Disc and to the dis-
tance, between the faint Longitudinal Lines.  4, Another Disc nearly detached.  5, A de-
tached Disc more highly magnified, showing the Sarcous Elements. 6,  Fibrillar separated
by violence from each other at the broken end of the Fiber. 7, 8, The two  appearances
commonly presented by the separated single Fibrillse ;  more  highly magnified, at 7 the
spaces are rectangular, at 8 the borders are scalloped and the spaces bead-like.
of an  inch, and  number  about  650  in each  ultimate  fiber.
They are unprotected by any covering,  while both the fasicu-
                 kto  too                     lus and ultimate fiber
            Fibrils of Human Muscle.              bPTS.--All the EQUS-
cles of the  body  are  divided into two  classes, according  to
their  function.    Those  necessary  for  carrying on  the  vital
functions,  such  as breathing  and digestion,  are  called  Or-
ganic,  and those  under  the  control  of the  will Animal Fi-
bers.   In addition  to  their  use  as  a  means  of  distinction,
they may  be known by their appearance under   the  micro-

  What is the Sarcolemma?  On what element of muscle is this wanting? 230. Giva
the two functional classes of the muscles. 
AND   PHYSIOLOGY.
109
Fig. 123.
 Transverse Section of Human Fibrillae
snowing a Polygonal form.
^cope, the Animal Fiber being
marked by  transverse  striae,
or stripes resembling a beaded
filament, called  Striped  Fi-
ber ;  and the Organic  being
made up merely  of flattened
bands destitute of these cross
marks,  and  hence called Un-
striped, or smooth fiber.   Th?
unstriped fibrils are developed
from cylindrical  or spindle-
shaped   nucleated  cells, and
are surrounded  by a peculiar
fluid known as  muscle juice,
which is unlike the plasma of
the  blood,   since  it  contains
casein.
   231.  Tendons,  Aponeuro-
ses,Bellyor Swcllof theMus-
clc.—The extremities  of th?
muscles are composed of denso
areolar tissue in the form  of
tendons or  cords,  and  that
extremity which is nearest  to
the center of motion is  called
Fig. 124.
 A broken Muscular Fiber showing the
sheath or myolemma untorn.
FiG. 125.
   Fusiform Cells of Smooth Muscular Fii
 bcr. _, Two cells in their natural state.
 i, A cell treated to acetic acid, showing the
 nucleus c.
ihe Origin, while the one most
 What is the appearance of the Animal Fibre under the microscope? Also that of tho
Organic? 231. State the composition of the Tendons. 
110           HITCHCOCK'S  ANATOMY

remote from it is called its Insertion.   These are exceedingly
firm and  strong, perfectly inelastic, and can not be torn from
the bones without unnatural violence.   If the extremity of
the muscle has  a large surface for attachment, its tendon is
expanded into a broad  membranous portion termed an Apo-
neurosis,  as may be  seen  in the muscles inclosing the abdo-
men ; while  the greater portion of the muscles have a fleshy
portion called the Swell or Belly, and the  tendinous portion
contracted into  the shape of a cord, or even of a thread.  In
general this belly of the  muscle is in a place which is the
most firmly fixed, and distant from the point to be moved,  in
order to effect grace of motion, and beauty of form.
                           Fig. 126.
A Radiate Muscle.
   232. Forms  of Muscles.—In form the muscles  present a
great diversity.   A  Radiate Muscle (Fig. 126)  is one where
the fibres radiate from a central portion  to  distribute them-
selves upon a large surface.   In the Fusiform (Fig. 127) the
                          Fig. 127.
A Fusiform Muscle.
fibres diminish in size from a center to each  extremity.  In

 What is the fleshy portion of the muscle called ? What is an A poneurosis ?  Define the
Origin and Insertion of a muscle.  Where is the Belly of the muscle generally located ?
232. Describe the Radiate and Fusiform Muscles. 
AND  PHYSIOLOGY.
Ill
Fig. 128.
                    A Doubly Penniform Muscle.
the Penniform the  fibres are short and arranged upon a long
tendinous line, like the plumes upon the quill of a feather.
The circular form, called Sphincter, is found in parts of the
b >dy where the  fibres  are circular, surrounding some orifice
which they partially or entirely close up by their contraction.
An example of this is  seen  around  the  eye and mouth.  A
few muscles resemble in  structure a ribbon.   Others a cord,
and others are very thin  and expanded, so that they resemble
a membrane.   All  these  forms are  thus  arranged to secure
the greatest amount of power with dispatch,  and also the most
perfect freedom of motion, as well as to adapt  themselves to
the amount of space furnished them on the skeleton.
   233.  Number of  Muscles,  Single  Muscles.—The number
of muscles in man is 540, being more than twice the number
of the bones.   They are nearly all arranged in  pairs ; that is,
both sides of the body  have similar muscles, while  the  single
or unmated muscles  are  only thirteen.  Each muscle is pro-
vided with  one or  more antagonist  muscles, or those  which
produce motion in an opposite  direction, save a  very few sur-
face muscles about the head and neck, where the elasticity of
the integuments produces the antagonistic motion.
   234.  Fascia.—Every muscle is  covered by a firm  and
slightly  elastic  membrane  called  Fascia,  which serves the
double purpose of keeping the fibres firmly in their place, and
also of producing  a tonic  pressure, which gives  increased
strength to the muscle.  An illustration of  the  utility of this
pressure is  seen in the  fact, that the school-boy, when engaged
in running as rapidly as  possible in his sports, ties a handker-
  Describe the Penniform and Circular Muscles.  Are there any other forms of muscles?
Why are muscles of these different shapes?  233. What is thenumberof humanmuscles?
How does this compare with the number of the bones?  How many unmated muscle!*
are there ? What is meant by antagonist muscles ? 234. What is the Fascia, and what
ourpose does it serve ?  What illustration of its use ? 
112
H I T-C HCOCK' S
ANATOMY
Fig. 129.
   Anterior View of the Muscles of the Body.
1,  Frontal Bellies  of the  Occipito-Frontalis.
2,  Orbicularis Palpebrarum.  3, Levator Labii
Superioris  Alaeque  Nasi.  4, Zygomaticus Mi-
nor.   5, Zygomaticus Major.   6, Masseter.  7,
Orbicularis Oris.  8, Depressor Labii Inferioris.
9,  Platysma-Myoides. 10, Deltoid.  11, Pecto-
ralis  Major.  12, Axillary portion  of the Latis-
simus  Dorsi.   13,  Sciratus
Major  Anticus.   14, Biceps
Flexor Cubiti.   15, Anterior
Portion of the  Triceps Ex-
tensor Cubili.   16, Supinator
Badii Longus.   17,  Pronator         J$>.fM
Eadii  Teres.   18, Extensor •   14.4.
Carpi Kadialis Longior.  19,
Extensor   Oasis  Metacarpi
Pollicis.  20,  Annular Liga-
ment.   21,  Palmar Fascia.
22,  Obliquus Extern us Ab-
dominis. 23, Linea Alba. 24,
Tensor Vagina; Femoris. 25,
Section   of  the  Spermatic
Cord.   26,  Psoas  Magnus-
27,  Adductor Lougue.   2S,
Sartorius.  29, liectus Fe-
moris.   30,  Vastus Exter-
nus.  31,   Vastus  Internus.
32, Tendon Patellar. 33, Gas-
trocnemius. 34, Tibialis An-
ticus.  35, Tibia.   36,  Ten-
dons  of the Extensor  Com-
munis. 
AND   PHYSIOLOGY.
113
  Posterior View of the Muscles  of the
Body.  1, Temporalis.   2, Occipital  por-
tion  of the Occipito-Frontalis.  3, Com-
plexus.  4,  Splenius.   5,  Massetcr.  6,
Sterno-Cleido Mastoideus.   7, Trapezius.
8, Deltoid.   9, lnfra-Spinatus.  10,  Tri-
ceps Extensor.  11, Teres Minor.  12, Te-
res Major.  13, Tendinous portion of the
           Triceps.   14,  Anterior Edge
           of the Triceps.   15, Supinator
           Kadii Longus.   16, Pronator
           Radii  Teres.   17, Extensor
           Communis Digitorum. 18, Ex-
           tensor  Ossis Metacarpi Polli-
Vo"
cis.  19, Extensor Communis Di-
gitorum Tendons.  20,  Olecranon
and Insertion of the Triceps.  21,
Extensor Carpi Ulnaris.  22, Au-
ricularis.  23,  Extensor Commu-
nis. 24, Latissimus Dorsi. 25, Its
Tendinous  Origin.  26, Posterior
Part of the Obliquus  Externus.
27, Gluteus Medins.  28, Gluteus
Magnus.  29, Biceps Flexor Cru-
ris.   30,  Semi Tendinosus.  31,
32,  Gastrocnemius.  33, Tendo-
Achilles. 
114
HITCHCOCK'S   ANATOMY
                                  chief about his waist in order
                                  to  give strength  to  his mus-
                                  cles.   And  so  important is
                                  this membrane to the  muscu-
                                  lar  system,  that,  upon  the
                                  thigh,   where   very   great
                                  strength   and   rapidity  of
                                  movement  is  required,  this
                                  membrane is  thicker than in
                                  most of the other parts of the
                                  body ;  and not only so, but a
                                  muscle is also provided for the
                                  especial purpose of rendering
                                  this  membrane   very   tense,
                                  when  any  violent  action is
                                  required, or its own elasticity
                                  is insufficient.
                                      235. Descriptions  of par-
                                  ticular Muscles.—In  such a
                                  treatise as the present one, it
                                  will of course be  impossible
                                  to describe all the  muscles as
                                  minutely  as  the bones  have
                                  been, nor will it be  necessary;
                                  but only those which  are the
                                  most interesting and instruc-
                                  tive.
   236.  Orbicularis Palpebral.—The muscle which surrounds
the eye is a sphincter which  is  made of circular  fibres, and
when contracted closes the eye, as it is  termed.   Consequently
this action requires  the movement of no bones, and no  attach-
ment to any thing but the soft parts of the face.   It is called
the Orbicularis Palpebrse.  Its antagonist is the Levator  Pal-
  What is said about the importance of this fascia upon the thigh ? 236. What is themus-
cle that opens and closes the eye, as it is termed?  What kind of a muscle is this!
What is the antagonist of the Orbicularis Palpebrae ?
  A Transverse Section of the Neck, show-
ing the Fascia Profunda, and its  Pro-
longations  as Sheaths for the Muscles.
1,  Platysma  Myoides.  2, Trapezius.  3,
Ligamentum Nuchas. 4, Sheath of Sterno-
Cleido-Mastoid.  5, Muscle itself.  6, Point
of Union of its Fascia. 7, Point of Union
of the Fascia  Profunda Colli of each side
of the Neck.  8, Section  of the Sterno-
Ilyoid Muscle.  9, Section of the Omo-
Ilyoid Muscle.  10, Section of the Sterno-
Thyroid Muscle.  11, Lateral Lobe of the
Thyroid Gland.  12. Trachea.  13, Oesoph-
agus.  14, Blood-vessels and Pneumogns-
tric Nerve in their  Sheath. 15, Longus
Colli.  16, Bectus  Anticus Major.   17,
Scalenus  Anticus.  IS,  Scalenus Medius
and Posticus. 19, Splenius Capitis.  20,
Splenius Colli.  21,  Levator Scapula.  22.
Complexus.  23, Trachelo - Mastoid.  24
Transversalis Cervicis. 25, Cervicalis D
scendens.  26, Semi-spinalis Cervicis.  2
Multifidus Spina?. 2S, A Cervical Vertebra. 
AND   PHYSIO 1, O G Y .
115
Fig. 132.
  A Front View of the Superficial Layer of Muscles on the Face and Neck.  1, 1, Ante-
rior Bellies of the Occipito-Frontalis.  2, Orbicularis or Sphincter Palpebrarum. 3, Na-
sal Slip of Occipito-Frontalis.  4 Anterior Auriculas.  5, Compressor Naris.  6, Levator
Labii  Superioris Aheque Nasi.  7, Levator Anguli Oris.  S, Zygomaticus  Minor.  9,
Zygomaticus Major.  10, Masseter.  11, Depressor Labii Superioris Alaeque Nasi.  12,
Buccinator.   13, Orbicularis Oris.  14,  The denuded  Surface of the Inferior Maxillary
Bone.  15, Depressor Anguli Oris.   16, Depressor Labii Inferioris.  17, The portion of
the Platysma Myoides that passes on to the Mouth, or the Musculus Bisorius. 18, Sternc-
Ilyoideus.  19, Platysma-Myoides.  It. is wanting on tho  other side of the Figure.  20,
Superior Belly of  the Omo-Hyoideus near its insertion.  21, Sterno-Cleido-Mastoideus.
22, Scalenus Medius-  23, Inferior Belly of Omo-Hyoid.  24, Cervical Edge of the Tra-
pezius.

pebras, which takes  its  origin far  back  on the  sides of the

cavity of the orbit, and is attached to  the  upper  lid.    When

contracted it  opens the eye.

   237.  Orbicularis  Oris.—The  Orbicularis  Oris  (circular

muscle of the face) by its contraction closes the  mouth.   Like

the corresponding muscle of the eye, it has its origin  and in-

sertion in the soft parts of the face, and is made  up of concen-

              237. Where is the Orbicularis Oris, and what is its use ? 
116
HITCHCOCK'S  ANATOMY
trie fibres.  And the antagonists are those muscles which are
inserted into it, coming  from  the different bones of the face
              3      _■
moving the lips and nostrils, and giving much  of the expres-
sion of emotion in the countenance.

   238.  Massetcr and  Temporal Muscles.—The elevators of
the lower  jaw are  two:  the Masseter (chewing)  and  the
Temporal  (from the bone  on which  it lies).   They are at-
tached to  the posterior portion of the bone near the joint, since
if their position was nearer to the front part of the bone they
would not  contract sufficiently to bring the jaws together.

   239.  Digastric  Muscle.—The lower jaw is carried down-
wards by the Digastricus (two bellies) musele.   This  is a long
round muscle  like  a cord,  which commences just below  the
lower front tseth, and from thence runs downwards and back-
wards to  ths  os hyoides, where it runs through a tendinous
loop ; after this it passes upwards  and backwards to  the mas-
toid  process upon  the temporal bone, just behind  the ear.
The contraction of this muscle then will open the mouth, when
the os hyoides  is made  fast;  but if the jaw be  confined by
its elevator muscles, the os  hyoides  will be the movable por-
tion, and will be elevated.   The necessity of such an  arrange
ment  is evident from the fact, that no muscle from the jaw to
the hyoides would  be of sufficient  length  to  open the  lower
jaw by its contraction; and if it were to  run backwards to
the spinal  column, the violence with which it must  contract
to accomplish its object, would produce such pressure upon the
vessels and nerves  of the neck as to injure  them.

   240.  Sterno-Cleido-Mastoideus.—A bow,  or bending of
the head upon the  spinal column, is effected  by the action of
the Sterno-Cleido-Mastoideus muscle (named from its attach-
 What are its antagonists? What muscles aid very much in giving expression to tho
countenance ? 23S. What arc the two pairs of muscles that bring the jaws together in
the act of chewing?  239. State the muscle that opens the mouth.  What mechanical
peculiarities in its structure and operation ?  Why the necessity of such a complicated
arrangement ? 240. What is the muscle by whose action wo bow the head ? 
AND   PHYSIOLOGY.
11-
Fig. 133.
  A Lateral View of the Deep-seated Layer of Muscles on the Face and Neck.  1, Tem-
poral Muscle deprived of its Fascia. 2, Corrugator Supercilii.  3, Nasal Slip of the Oc-
cipito Frontalis. 4, Superior or Nasal Extremity of the Levator Labii Superioris Alaeque
Nasi.  5, Compressor Naris.  6, Levator  Anguli Oris.  7. Depressor Labii Superioris
Alaeque Nasi.  8, Buccinator.  9, Orbicularis Oris. 10, Depressor Labii Inferioris. 11,
Levator Labii Inferioris.  12, Anterior Belly of the I)i_:istricns.   13, Mylo-Hyoid. 14,
Stylo-Hyoid.  15, Thyro-Hyoid.  16, Upper Belly of the Omo-Hyoid.  17, Sterno-Cleido.
Mastoid. IS, Sterno-IIyoid.  19. Scalenus Anticus.  20, Pectoralis Major.  21, Deltoid.
22, Trapezius.  23, Scalenus Medius. 24, Levator Scapulas and Scalenus Posticus. 25,
Splenius.  26, Complexus.

ment to  the  Sternum,  Clavicle,  the Greek for which is kleis,

and the  mastoid process).   The form  of this muscle is essen-

tially that of a thick ribbon.

   241.  Muscles  of  the  Scapula—The  Scapula is  covered

with muscles  on both sides, most  of which are inserted  into

the head of the  humerus.   Their use  is to  rotate  the  hu-

  What is the shape of this muscle ?  241. What  actions do the muscles of tha scapuh
effect? 
118              v 7, 71 c ii c o c i- ' s   anatomy

                                  Fig. 134.
  A View of the Muscles of the Back as shown after the removal of the Integuments.  1
Occipital Origin of the Trapezius.  2, Sterno-Cleido-Mastoideus.  3, Middle of the  Tra-
pezius. 4, Insertion of the Trapezius into the Spine of the Scapula.  5, Deltoid.  6, Sck.
ond Head of the Triceps Extensor Cubiti.  7, Its Superior Portion.  8, Scapular port:; n
of the Latissimus Dorsi.  9, Axillary Border of the  Pectoralis Major.  10, Axillary Bor-
der of the Pectoralis Minor.  11, Serratus Major Anticus.  12, Infra-Spinatus.  13, Teres
Minor. 14, Teres Major.  15, Middle of the Latissimus Dorsi.  16, External Oblique of
the Abdomen.  17, Gluteus Medius.  IS, Gluteus Minimus.  19, Gluteus Magnus.  ?0,
Fascia Lumborum.


merus,  as  well  as to  give  it  protection  where  it  articulates

with the scapula,  and to  keep it in its place. 
AND   PHYSIOLOGY.
119
   242.  Biceps.—The  Biceps               Fig. 135.
(two  heads, or points  of at-
tachment) is the muscle which
flexes or  bends  the arm to-
wards  the   body.   It  arises
from the head of the humerus
and scapula,  and  is  inserted
into  the  upper  end  of  the
radius.   It is a very fine ex-
ample of a  fusiform muscle,
and  though acting at  a great
mechanical disadvantage as to
power, it effects a rapid move-
ment.
   243.   Triceps.—The   Tri-
ceps (three heads), its antag-
onist, is similar in its general
form, and is attached  to the
ulna  instead  of  the  radius.
It is situated upon the poste-
rior side of  the humerus, and
the force with which  it  may
be made  to contract,  is  seen
in the  powerful  blow  given
by the  boxer, or  the weights
raised by extending the  arms
upon the instrument made for
the purpose in a gymnasium.
   244. Muscles of the  Forc-
A r in.—The Fore-Arm is abun-
dinous  Insertion of the Pectoralis Minor.
the Biceps. 13, Latissimus Dorsi.  14, Inner portion of the Triceps. 15, Body of the
Biceps. 16, Outer portion of the Triceps. 17, Brachialis Internus.  18, Origin of the
Flexor Muscles.  19, Brachialis Internus near its Insertion.  20, Tendon of the Biceps.
21, Fasciculus from  the Biceps Tendon to the Fascia Brachialis.  22, Flexor Carpi Ea-
dialis.  23, Palmaris Longus. 24, Supinator Radii Longus.______________^_________
  242. Why is the name Biceps given to the  muscle that flexes the fore-arm ?  What
mechanical disadvantage in its structure ? What gain from it?  213.  What is the antag-
onist of the Biceps ?  What actions show its mode of action ?
                               (J
  A View of the Muscles on the Front of
the Arm. 1, Clavicle. 2,  Coracoid Pro
cess and Origin of the Short Head of the
Biceps.  3, Acromion Scapulas.  4, Head
of the Os Humeri.  5, Tendon of the Bi-
ceps Muscle in the Bicipital Groove.  0,
Ligamentum Adscititium dissected off.  7,
Cut portion of the  Pectoralis Major.  8.
Long Head of the Biceps.  9, Insertion of
the Deltoid.  10, Cut portion of the Ten-
11, Coraco-Brachialis. 12,  Short Head of 
120
HITCHCOCK'S   ANA T O M Y
Fig. 136.
 A View of tho Outer Layer of the Mus-
cles on the Front of the Fore-Arm (Flex-
ors).  1,  Lower portion  of the  Biceps
Flexor Cubiti.  2, Brachialis Internus. 3,
Lower Internal portion of the Triceps. 4,
Pronator  Eadii Teres. 5, Flexor  Carpi
Eadialis.  6,  Palmaris Longus. 7, Part of
the Flexor Sublimis Digitorum. 8, Flexor
Carpi Ulnaris. 9, Palmar Fascia.  10,
Palmaris  Brevis Muscle.  11, Abductor
Pollicis Manus. 12, Portion of the Flexor
Brevis Pollicis Manus.  The Line crosses
t_e  Adductor Pollicis.  13, Supinator
Longus.   14, Extensor  Ossis Metacarpi
Pollicis.

order that the  fingers may be
desirable that there should be  a
 dantly supplied with muscles
 many of which  are fusiform
 in their  appearance,  and all
 of which are  for the purpose
 of moving  the  hand and fin-
           es
 gers.  Most of  the fibres run
 in a direction parallel to the
 bones of the  fore-arm,  but
 those Avhich  perform the ac-
 tions of pronation and supina-
 tion lie   obliquely,  and  some
 nearly at right  angles to the
 long  muscles.    In this  part
 of the body  the muscles are
 distinguished  by slenderness
 of form and consequent deli-
 cateness of tendon,  the  latter
 in many  cases being equal in
 length to the muscular fibre,
 since there are very few mus-
 cles below the wrist, and those
 only  which  are  short  and
 thick, for the purpose of mov-
 ing   the   thumb  and   little
 finger.
    245.  Tendons of the  Fin-
 gers.—The  arrangement of
 the   tendons  which  are  at-
 tached  to the  phalanges, for
 the  motion  of  the  fingers,
 shows  the  contrivance  and
 skill of an  Infinite  Being. In
slender and easily moved,  it is
s small a quantity of matter in
 244. Give the general arrangement of muscles iu the fore-arm.  How do the Pronator*
and Supinators lie? 
       and   physiology.               121

Fig. 137.                          Fig. 138.
                               1, Internal Lateral Ligament of the El-
bow-Joint. 2, Capsular Ligament of the Elbow-Joint.  3, Coronary Ligament of the
Head of the Radius.  4, Flexor Profundus Digitorum Perforans.  5, Flexor Longus
Pollicis.  6, Pronator Quadratus. 7, Adductor Pollicis Manus.  8, Lumbricales. 9,
Interossei.
them  as  possible.   Hence,  as above stated, the muscle  that
moves  them is situated  in the  fore-arm, and the  tendon  i3
made as slender as possible.   But  here  another  arrangement
claims our attention.   A set of four tendons from a common
muscle is attached to  the  base  of the second phalanx of each
finger,  and  a second  set to the third row of phalanges.   The
question  then  arises, how can these  two  tendons pass upon
245. Describe the arrangement of the tendons of the fingers. 
 1??           HITCHCOCK'S   A N A T O M Y

 both  sides  (upper  and lower)  of the  finger and  be firmly
 enough secured to the finger to  keep them in  place, without
 making the finger of an unwieldy bulk, and at the same time
 allow the force to be  applied upon the  center of  the  finger
 rather than upon one side ?  The answer is this : the muscle
 which sends its tendons to  the second phalanx  Kes  above the
 other set of tendons, and where  the superior tendons join tl._
 second  phalanx, they are each  split  into  two  parts, through
 which the tendons of the lower muscle pass to the  last  pha-
 lanx, and move freely without interruption from the superior
 muscle or tendons..   This  arrangement is  found in the foot,
 as well as in  the  hand, for giving the same  motion to the
 toes,  and very much  resembles  the  movement  of a  cord
 through a loop.
   246. Muscles of  the Thumb  and  Little  Finger.—The
 thumb  and little finger, as already mentioned, are supplied
 with separate muscles in the body of the hand, mainly for the
 purpose of giving motion from side to side,  as  well as a partial
 rotation.  In addition to this, there are several muscles  upon
 the fore-arm which  give their tendons only to these two  ex-
 tremities.   The obvious  use of this  arrangement is to  give
 strength  and  great  variety of motion  so necessary in  the
 thumb and little finger.
   247. Muscles of  the Back,  Dorsal   Muscle.—Upon  the
 back are found at least thirty pairs of muscles, which are ar-
 ranged in six layers.   These are of various forms and  sizes,
 with complicated and obscure attachments.  The main use of
 these muscles, taken as a group, is to  keep the trunk in an
 upright position, and give  a firm attachment for muscles to
 move the extremities.   The outermost layer  is very super-
 ficial, lying directly under  the  skin, while  the  deepest  layer
 is deeply imbedded between different processes of the  vertebras.
  Why must one tendon pnss through another rather than pass along by its side?
 Do wo find this arrangement upon both hands and feet? 246. Which two extremities
 of the hand have the most muscles given to them?  247. How many pairs of muscles
 upon the back of the body?  Give tho numbor of layers into which they may be dis-
»ecfced.  State the essential purpose of them. 
AND   PHYSIOLOGY.
121
Fig. 139.
  A Viev of the Second Layer of Muscles of the Back.  1, Trapezius.  2, A portion of
tho Tendonous ellipse formed by the Trapezius on both sides.  3, Spine of the Scapula.
4, Latissimus Dorsi. 5, Deltoid.  6, Infra-Spinatus and Teres Minor.   7, External Ob-
lique of the Abdomen.  8, Gluteus Medius.  9, Gluteus Mh_iius of each side.  10, Leva-
tor Scapulfe.  11, Uhomboideus Minor.  12, Ehomboideus Major.  13,  Splenius Capitis.
14, Splenius Colli.  15, A portion of the Origin of the Latissimus Dorsi.  16, Serratus In-
ferior Posticus. 17, Supra-Spinatus.  IS,  Infra-Spinatus.  19, Teres Minor.  20,  Teres
Major.  21, Long Head of the Triceps Extensor Cubiti. 22, Serratus Major Anticus.  23,
Internal Oblique of the  Abdomen.

The largest muscle of the back (hence  the name Dorsal) is

of value to move the arnn.   It  has its origin  from  the  lum-

bar and sacral vertebras, and the  posterior  third  of  the crest

of  the ilium,  and is inserted by a short  tendon  into the upper

extremity of the  humerus.   The action  of this muscle brings

        Give the origin and insertion of the Dorsal muscle.  State Its action. 
124
HITCHCOCK'S  ANATOMY
 the arm downwards and backwards, as in the movements of
 chopping wood or striking with the blacksmith's sledge.   But
 when the hands are made the fixed points, the body is raised
 upwards.

   248.  Superior and Inferior  Serrali.—Two muscles of the
 back are used in forced or violent respiration.   These  are tho
 Superior and  Inferior Serrati Muscles.  The Superior Ser-
 ratus arises from the three lower cervical and two upper dorsal
 vertebrae, and runs downwards  and  forwards to be inserted
 into the border of the second,  third, and fourth ribs.  The
 Inferior Serratus arises from  the last  two dorsal and three
 upper lumbar vertebras, and, running upwards  and forwards,
 is inserted upon the four lower ribs.   The name of these mus-
 cles means in Latin " saw-like," since the portions which join
 upon the ribs  resemble the  teeth of  a  saw.   The  former of
 these elevates the ribs, thereby enlarging the cavity  of the
 chest,  while the latter assists in its compression by depressing
 the ribs, and  consequently the diaphragm, downwards.

   249. The  Diaphragm.—But the essential  muscle of respi-
 ration is the Diaphragm.  This,  as its name implies, is  a par-
 tition  across   the  body just  below the  lungs. —with   three
 large openings,—which separates  the thorax°from the abdo-
 men.   Its  attachments in general terms may be said  to be
 upon  an oblique line  drawn about the body just below the
 ribs, which line intersects the first  lumbar  vertebra,  where
 the central  tendon of  the Diaphragm, as it is termed, is at-
tached.   When relaxed, it presents the  appearance of  an in-
verted and irregularly shaped cup or  basin, but when in a
state of contraction it becomes nearly a plane surface.   Hence
this muscle enlarges the chest by depressing its lower surface,
thereby forming a partial vacuum.
 248. Which muscles of the back are used in forced respiration ?  Give the origin and
insertion of the two Serrate Muscles.  Why called "Serrate?" 249. Give the form of
the Diaphragm.  What two cavities of the body docs it separate?  What is it an essen-
tial agent In effecting ? 
AND   PHYSIOLOGY.
124
Fig. UO.
  A View of the Under Side of the Diaphragm.  1, 2, 3, The Greater Muscle of the Dia-
phragm inserted into the Cordiform Tendon.  4, The small triangular space behind tho
Sternum, covered only by Serous Membrane, and through  which Hernia sometimes
pass.  5, Ligamentum Arcuatum of the Left Side. 6, Point of Origin of the Psoas Mag-
nus.  7, A small Opening for the Lesser Splanchnic Nerve.  8, One of the Crura of the
Diaphragm.  9, Fourth Lumbar Vertebra.  10, Another Crus or portion of the  Lesser
Muscle of the Diaphracm. 11, Hiatus Aorticus.  12, Foramen G_sophageum.  13, Fora-
men Quadratum.  14, Psoas Magnus Muscle.  15, Quadratus Lumborum.
   250. Intercostal Muscles.—Between  the ribs  are  placed
two sets of muscular fibres, an external and  an internal, called
the Intercostal Muscles, which by their action  draw the ribs
upwards.   The fibres run  in  a diagonal direction from one rib
to another, so that the greatest length may be given for their
contraction without compromising too  much  of their power.
And hence we can see that while the first rib is firm and im-
movable, by contraction of these fibres the ribs must be raised,
and by their relaxation they must  be depressed.  The  exter-
nal fibres run downwards and towards the middle line  of the
abdomen, while the internal run downwards and backwards.
   251. Abdominal Muscles.—The principal muscles  of the
abdomen  are  large and thin expansions  of muscular  fibres,
  250. Give the arrangement of fibres in the Intercostal Muscles.  251. What forms tho
principal part of the walls of tho abdomen ? 
126
HITCHCOCK'S   ANATOMY
            FlG- 141.               which  completely  cover  tho
                                  space below the border of the
                                  ribs, and above the innomina-
                                  tum.    They are arranged un-
                                  der four different names, since
                                  they  run  in  different  direc-
                                  tions as they encircle the ab<
                                  domen.   By their  contraction
   (|- "---^   ~" - b*wf           they press upon the digestive
                                  organs, and thus diminish the
                                  cavity  of  the  abdomen, and,
                                  in proportion to the  elasticity
                                  of the diaphragm,  the thorax
                                  also.    Hence  these  are the
                                  essential instruments in cough-
                                  ing,  laughing,   crying,   and
                                                     as in  sing-
                                                  or  any action
                                  requiring expulsive effort. By
                                  their elasticity they also per-
                                  form  the function  of expira-
                                  tion  in natural breathing, as
                                  well as  keep  up a tonic  pres-
                                  sure   upon  the  stomach  and
                                  alimentary canal.
                                    252.  Great  Psoas Muscle.
                                  —The  Great Psoas  Muscle,
                                  known in animals as the  ten-
                                  der  loin   (from the  Greek
                                  signifying   a  loin),  is   the
     which  bends the thigh upon,  or  towards the  trunk.
It has its origin from the last dorsal  and four upper  lum-
bar  vertebrae,  and  passes from  thence  downwards  and  for-
wards, gliding over  the edge of the innominatum, and attaches
sneezing, as well
     shouting,
in
  A Lateral View of the Muscles of the
Trunk, especially on  the  Abdomen. 1,
Latissimus Dorsi. 2, Serratus Major An-
ticus. 3,  Upper portion of the External
Oblique.  4, Two of the External Inter-
costal Muscles.  5, Two of the  Internal
Intercostal Muscles.  6, Transversalis Ab-
dominis.  7, Fascia Lumborum. 8, Poste-
rior part of the Sheath of the Rectus, or
Anterior Aponeurosis of the Transversalis
Muscle.  9, The Rectus Abdominis cut off
and in its Sheath. 10, Rectus Abdominis
of the Right Side.  11,  Crural Arch. 12,
Gluteus Magnus—Medius and Tensor Va-
gina) Femoris covered by the Fascia Lata.
one
 Under how many heads aro they arranged ?  What actions do they accomplish when
contracted?  252.  What is the scientific name of the "tender loin?"  Give its attach-
ments. 
and   physiology.                  12 t

           Fig. 142.
  A View of the Superficial Muscles of the Left Side, and of the Deep Muscles of th«
Right Side, on the  Front of the Trunk.  1, Pectoralis Major.  2,  Deltoid.  3, Anterior
Edge of Latissimus-Dorsi.  4, Serrated Edge of Serratus Major  Anticus.  5,  Subclavius
Muscle.  6, Pectoralis Minor.  7, Coraco-Brachialis.  8, Biceps Flexor Cubiti.  9, Cora-
coid Process of the Scapula.  10,  Serratus  Major Anticus after the removal of the Ob-
liquus Exterrius Abdominis.  11,  External  Intercostal  Muscle of the Fifth  Intercostal
Space.  12, External Oblique of the Abdomen.  13, Its Tendon.  The Median Lino is tha
Linea Alba.—The Line to the Right of the  Number is the Linca Semilunaris.  14, Tho
portion of the Tendon of the External Oblique, known as Poupart's Ligament.   15, Ex-
ternal Abdominal Ring.  16, Rectus Abdominis.  The Whito Spaces are the Linea Trans-
versa.  17, Pyramidalis.  18, Internal Oblique of the Abdomen.  19, Common Tendon
of the Internal Oblique and Transversalis.  20, Crural Arch.  21,  Fascia Lata Femoris.
22, Saphenous Opening. The Crescentic Edge of the Sartorial Fascia is seen just abov*
fig. 22, and the Interior or Pubic Point of the Crescent is known as Hey's Ligament.


itself to the  front part of  the lesser trochanter process of  the

femur.    It is  made up of a very compact band of fibers,  and,

though  acting  at  a great mechanical   disadvantage, it is ca-

pable of moving the lower extremity  with  great  power.    By

                                    6* 
128
HITCHCOCK'S  ANATOMY
253.
Gluteus  Muscle,
   Fig. 143.
}his muscle it is that the body is bent forward when the thigh
is fixed, and also by its means we  keep  the body erect when
in a sitting posture.
                            -A movement in a direction  oppo-
                                 site to the  last  muscle, is ef-
                                 fected by the contraction of
                                 the  Gluteus  muscle.    This
                                 has its origin and insertion at
                                 points  directly   opposite  to
                                 those of  the psoas  muscle—
                                 and  forms  the  nates or but-
                                 tock.  The fibers of this mus-
                                 cle are the  coarsest of any in
                                 the whole body,  showing that
                                 they are designed for strength
                                 and  not  celerity of motion.
                                 Besides the movement already
                                 mentioned,  this  muscle  is of
                                 great value when the  leg  is
                                 made  firm  by  keeping the
                                 body in  an  upright position,
                                 or raising the body upon the
                                 thighs when it is bent forward.
                                    254.    Muscles   of   the
                                 Thigh.—The  leg (Tibia)  is
                                 moved upon the  thigh  (Fe-
                                 mur) by the conjoint  action
                                 of  four muscles.    These have
                                 their origin about the head of
                                 the femur, and the lower por-
                                 tion of the innominatum, and
                                 all  unite  into  one  tendon
                                 which  is  inserted upon the
                                 tubercle,  or  process  of the
  A View of the Muscles on the Front of
She Thigh.  1, Crest of the Ilium. 2, Its
Anterior Superior  Spinous Process.  3,
Gluteus Medius. 4, Tensor Vaginae Fe-
moris.  5, Sartorlus.  6, Rectus Femoris.
7, Vastus Externus.  8, Vastus Internus.
9, Patella. 10, Iliacus Internus.  11, Psoas
Magnus.  12, Pectineus.  13, Adductor
Longus. 14, Adductor Magnus. 15, Gra-
cilis.
  What movements are effected by it?  253. What muscle produces motion in a con-
trary direction to the psoas muscle ? What is said of the size of the fibers of the Ghiteus ?
2o4. How many muscles act to extend the tibia or the femur? 
AND  PHYSIOLOGY.
129
tibia near to its upper extremity.   Spoken of together, these
muscles are called  the Quadriceps Extensor  Femoris.   The
tendon is one of the  strongest in  the  body, and has inclosed
within it  the patella, which bears  the same  relation to the
tendon as the pulley does to the  cord which  passes over it.
The action of these muscles extends the leg, as in walking,
running, or lifting the foot, and also places the femur in a lino
above the tibia, when the latter is made the  fixed point.

   255.  Sartorius  Muscle.—The  Sartorius or Tailor's mus-
cle is a very  long and slender muscle commencing at the an-
terior portion of the innominatum, and, descending downwards
and inwards, is inserted into the upper part of the  inside of
the tibia.   The obvious action of this muscle will be to bend
the leg  somewhat backwards, and then  to  carry it across its
fellow, as is done by the tailor when seating himself for work
on his bench.

   256.  Tensor  Vagina;  Femoris.—A muscle already alluded
to—the Tensor Vaginae Femoris, or stretcher of the sheath of
the thigh—arises at the upper  and  front portion of the inno-
minatum, and is inserted into the very strong fasciae of the
thigh, its use being to assist the muscles in their  action, by
increasing the tonic pressure upon  them.

   257.  Muscles  of the  Posterior Part  of  the  Thigh.—
The muscles  found  upon  the posterior part of  the femur
and antagonizing the  compound  muscle  in  front, are four in
number, taking their origin from the ischium  and pubes, and
beino- inserted into the broad head of the  tibia.   Their  ten-
dons make those portions of the thigh which  are  familiarly
known  as  the  ham-strings.  Their names are  the Biceps,
Gracilis, Semi-tendinosus and Semi-membranosus.
 When taken together, what is the muscle called ? What bone is imbedded in the ten-
don of the Quadriceps Extensor Femoris ? 255. Describe the Sartorius or Tailor's mus-
cle.  256. What is the Tensor -Vaginas Femoris of service for?  257. How many muscles
act as antagonists to the Quadriceps, etc. ?  Give their names. 
130
HITCHCOCK'S   ANATOMY
Fig.  144.
Fig.  145.
  A View of the Muscles on the Back of
the  Thigh.  1, Gluteus Medius.  2, Glu-
teus Magnus.  3, Fascia Lata covering the
Vastus  Externus.  4, Long Head of the
Biceps.  5, Short Head of the Biceps. 6,
gemi-Tendinosus. 7,7, Semi-Membranosus.
8, Gracilis.  9, Edge of the Adductor Mag-
nus.  10, Edge of the Sartorius.  11, Pop-
liteal Space.  12, Gastrocnemius.
  A View of the Muscles on the Front of
the  Leg.  1,  Tendon of the Quadriceps
Femoris. 2, Spine of the Tibia.  3, Tibi-
alis Anticus. 4, Extensor Communis Digi-
torum.  5, Extensor Proprius Pollicis.  6,
Peroneus Tertius.  7, Peroneus Longus.
8, Peroneus Brevis.  9, 9, Borders of the
Soleus.  10, Portion of the Gastrocnemius.
11, Extensor Brevis Digitorum.
   258.  Muscles  of  the  Anterior  Part  of  the  Leg.—Upon
the anterior portion of the  Tibia, or leg proper, are found four
muscles with slender tendons,  which are for the upward move-
ment or flexion of the foot.   They  have their origin  near the
head of the tibia, and are inserted into the  bones of the meta-

  258. Where are the four muscles located  that bend the fost upward ?  Give their origin
and insertion. 
AND   PHYSIOLOGY.
131
tarsus and phalanges.   Their
names are the  Tibialis  Anti-
cus, Extensor  Longus  Digi-
torum,  Peroneus Tertius, and
Extensor Proprius Pollicis.
   259.  Muscles of  the Pos-
terior Part  of the Leg—The
muscles on  the  reverse por-
tion of the leg are three, con-
stituting what is known as the
calf of the leg.    They are the
Gastrocnemius, Plantaris, and
Soleus.   They are attached to
the  top of the tibia on its pos-
terior side, as well  as to  the
lower part of the femur, and
all form a conjoint tendon, the
largest in the body, and which
is attached to the bone of the
heel.   It is called the tendon
of Achilles, because  the great
Grecian warrior is said to have
been killed by the wound  of
an arrow at this point.  The
use of these muscles is to raise
the body  upon tho  toes, and
are the muscles which are  of
the greatest value to us in the
act of walking.   Immediately
beneath these muscles are six
an opposite direction to those
leg.   They are attached near
fibula, and  inserted  into the
 259. State the muscles which constitute
les, and why is it so called ?  IIow many
leg?
Fig. 146.
    A View of the Muscles on the Back of tho
  Leg.  1, Tendon of the Biceps. 2, Inner
  Hamstring  Tendons.  3, Popliteal  Space.
  4, Gastrocnemius.  5, Soleus. 6, Tendo-
  Achilles. 7, Its Insertion on the Os Calcis.
  8, Tendons of the Peroneus Longus and
  Brevis.  9,  Tendons of the Tibialis Posti-
  cus and Flexor Longus Digitorum  behind
  the Internal Malleolus.
others which produce motion in
upon the anterior  portion of tha
the upper part of the  tibia and
metatarsal bones  and  the  pha-
the calf of the leg.  What is Tendon of Acini-
muscles lie deeply covered in the calf of the 
132
HITCHCOCK'S  ANATOMY
langes.   In the tendon of one of them (Peroneus  Longus) is
found a sesamoid bone, at the  point where it glides over the
cuboid bone.

   260.  Muscles  of  the  Foot.—A  fewT  muscles are  found
upon the upper and under surface  of  the  foot, most of which
           F   147              arise  near the tarsus, and are
                                inserted  at  the  base  of tli3
                                phalanges.    In  their  action
                                the toes  are either bent  or
                                extended.
                                   261. Annular Ligaments.
                                —An interesting  contrivance
                                for preserving the slenderness
                                of the  hand and foot is found
                                in the Annular  Ligaments.
                                These  are  large  bundles  of
                                ligamentous tissue which pass
                                around the  wrist and  ankle,
                                very much resembling a brace-
                                let.   (Figs. 148, and  149, p.
                                133.) They are very firm and
                                stout, and their  design  is  to
                                keep   in   place  the tendons
                                which  move  the extremities.
                                When,  for example, we  move
                                the toes upwards, the muscles
                                which effect this motion with
their tendons would extend in a straight line  from  the upper
part of the  tibia to the last phalanx,  thus  making the  leg
and foot very cumbersome and  unwieldy organs, and poorly
adapted to their present use.
 A View of the Muscles on the Sole of the
Foot immediately under the Plantar Fas-
cia.  1, Os Calcis. 2, Section of the Fascia
Plantaris. 3, Abductor Pollicis. 4,  Ab-
ductor Minimi Digiti.  5, Flexor  Brevis
Digitorum.   6, Tendon  of the Flexor
Longus Pollicis.  7, 7, Lumbricales.
 261. What is the use of the Annular Ligaments ? What ornaments do they very closely
jesemble'l  Suppose these or their equivalent was wanting ? 
AND    PHYSIOLOGY.
133
Fig. 148.
  A View of the  Outer Layer of Muscles
on the Back of the Fore-Arm (Extensors).
1, Lower portion of the Biceps Flexor.  2,
Part of the Brachialis Internus.   3, Lower
part of the Triceps Extensor.  4, Supinator
Radii Longus.   5, Extensor Carpi Radialis
Longior.   6, Extensor Carpi Radialis Bre-
vior.  7, Tendinous Insertions of these two
Muscles.   8, Extensor  Communis Digito-
rum.  9,  Portion of the Extensor Communis Digitorum called  Auricularis.  10,
Extensor Carpi Ulnaris.  11, Anconeus.  12, Portion of the Flexor Carpi Ulnaris.
13, Extensor Minor Pollicis.  The Muscle nearest the Figure is the Extensor Ossis
Metacarpi Pollicis.  14, Extensor Major Pollicis.  17, Posterior Annular Ligament,
The distribution of the Tendon3 of the Extensor Communis is seen on the backs of
the Fingers.
  A View of the Muscles on the Front ol
the Leg.   1, Tendon  of the  Quadriceps
Femoris.  2, Spine of the Tibia.  3, Tibi-
alis Anticus. 4, Extensor Communis Digi-
torum.  5, Extensor Proprius Pollicis.  6,
Peroneus  Tertius.  7,  Peroneus  Longus.
8, Peroneus Brevis   9, 9, Borders of the
Soleus.  10,  Portion of the Gastrocnemius.
11, Extensor Brevis Digitorum. 
134            HITCHCOCK'S   ANATOMY.
FUNCTIONS  OF  THE  MUSCLES.
FiG. 150.
a
I
X 262. Irritability of Muscular Fiber.—Muscular fiber has
 one characteristic peculiar to this  tissue.   This is  known as
 Irritability or  Myotility,  the shortening of the fiber when a
 stimulus  is  applied.   The  stimulus  may  be mechanical, as
 when the legs  of a  grasshopper are irritated with a probe or
 some pointed instrument, it produces  contractions.  Electric
 and  galvanic  currents, also, when  made to pass  interrupt-
 edly through any muscular portions of the body produce con-
 tractions ;  as when  a person grasps the handles of an electro-
 tome or seizes  the ball of a Leyden jar.   And  lastly, vitality
 is a muscular stimulus.
                      263.  Condition of the Fibrils in a State
                   of Contraction.—Formerly it was supposed
                   that muscular contractions were due to a
                   zig-zag position which was assumed by the
                   fibrils ;  but microscopical  examination has
                   proved that the shortening of the fiber  is
                   owing  to a change in  the  diameter of the
                   ultimate fibrils;  the  cell  in the fibril at
                   rest having its longest diameter  parallel to
                   the  fiber, while in a state of contraction the
                   longest diameter is at right angles to this.
                      264.  Tonicity.—Another   characteristic
                   of muscular fiber is Tonicity.   This  is a
                   constant strain  or  stretch of the muscular
                   fiber, while irritability or contractility only
                   manifests itself when a stimulus is applied.
                    This is a property which is exhibited when
                    a bone is broken or some muscular fibers
                    are separated.   Thus, when a cut is made
 Structure of the Fi-
brillse.  a, A fibril in
the state of ordinary re-
laxation,  b, A  fibril
partially contracted.
 262. What is the prominent characteristic of muscular tissue?  Illustrate the mechan-
ical, electric, and vital stimuli. 263. How do the cells of the fibrils arrange themselves
during a contracted state? 264. What is understood by Muscular Tonicity? When is
this only manifest? 
AND  PHYSIOLOGY.
135
directly acros3 the fibers the gash at once opens very widely;
or if a bone is broken and the ends allowed to slide by each
other, it is only by great force that they can be brought back
to their proper places.   The value of this property is seen in
keeping  the muscles in a state ready for action, as well as in
assisting the ligaments to keep the joints firmly together.

   265. Dependent  on Vital Energy.—Both of these charac
eristics are dependent upon nervous or vital energy.   For if
life be extinct,  or the  nerve proceeding  to any muscle be  cut
off, tonicity and irritability soon cease ;  although they remain
for a longer time in the involuntary than the voluntary mus-
cles.   As, for example, the hsart of a  sturgeon, after its re-
moval from the body,  has been known not only to pulsate for
a short time, but  even to keep  up its action  until  its folds
fairly rustled from inherent dryness.

   266. Muscular  Waste  the  Cause of  Muscular Contrac-
tion.—But here the question meets us, What is this power that
passes through the nerves to each fibril, and how does it energize
the muscle ? Is it a fluid acting on the fibers in the same manner
that water  acts upon the strands of a rope, or is it an impon-
derable agency, like electricity or heat, passing through  the
nerve by polar attraction or conduction from particle to par-
ticle ?   At present we must rest with the facts of muscular
movement,  and  perhaps we can never  solve the mystery in
this world.   The nature  of what we vaguely denominate
nervous or vital force  has never been determined.   No mys-
tery in religion exceeds that of muscular movement.   It how-
ever seems to be the case that muscular contraction is in a good
degree dependent on  a due degree  of  arterialization of the
iblood ; for if a muscle be placed in carbonic ac d its irritability
soon ceases, while in oxygen it remains  a long time after it is
removed from the body.  A want of the proper amount of oxy-
 Of what use is this property? 265. Upon what do both myotility and tonicity depend?
In which muscles do they remain the longest after death ? Instance the heart of the stur>
geon.  266. What is all we know of the power that produces this contraction ? 
136
HITCHCOCK'S   ANATOMY
         gen is the cause of the inability to exertion experienced in the
         chin air of mountain tops and the relaxation of the muscles  in
         fainting from exposure to carbonic acid, ether, or chloroform.
         On the other hand, the more full the respiration, t!;e more ener-
         getic the muscular power.    The effect of oxygen  upon the tis-
         sues is that of waste, or a consumer  ; that is, it produces a more
         rapid circulation  of matter  by removing the carbonic acid,
         and substituting itself in its place ; and the deeper the resjU
         ration, the more  energetically will all the functions  of the
         body be carried on.   Hence a plausible theory offers  itself
         to explain the cause of muscular  contraction, which is, that
         " muscular contraction is the necessary physical result of mus-
         cular disintegration."

            267.  The  Mechanical   Disadvantage   at  which   many
         Muscles  Act—The  Reason of   it.—The force of muscular
         contractions is  almost  always very great, sometimes so pow-
         erful  that  some of  the fibers are  ruptured.  But  the main
         evidence of this great force is exhibited in the mechanical  dis-
         advantage at which most of the  muscles  act.  For  instance,
                       Fig. 151.                  if the  muscles were
                                                 attached at c, a much
                                                 greater weight could
                                                 be lifted by the  ex-
                                                 penditure of the same
                                                 power than if it were
         attached at b ; but a  much longer portion of time would be
         necessary to  produce contraction  in such a length of fiber, a
         c,  than in a shorter portion, a b.   Besides, in  most cases  ifc
*        would be quite impossible for the  muscles to contract suffi-
         ciently to. effect what  they now do, since  muscular  fiber  can,
         not shorten itself  more than one third of its whole length, a_
         measured when uncontracted, or in  a state of rest.
 What, however, do we know about deficiency of oxygen as affecting these properties?
Instance ether and chloroform also. What hypothesis has been suggested owing to the
waste produced by oxygen ?  267. How is muscular power well illustrated? What loss
and what gain are both experienced by this construction ?
 
AND  PHYSIOLOGY.
137
Fig. 152.
 Muscular Fiber contracting
part, b, Contracted part.
a, Uncontracted
   268. Contraction commences at one  End — Only a Part
of the  Fibrils in a  State of Contraction  at Once.—The
contraction of a muscle does not take place in all parts of the
fibers at the same time, but commences at  one end, and con-
tinues through in regular
order, as  is seen  in the
cut 152.   It is  also sel-
dom the case that  all the
fibers  are contracted  at
once.   This explains the
reason why insane  people
are often so  prodigiously
strong, since the whole of  the  muscle is made to act at once.
It also shows us  why we can keep a muscle  contracted for a
long  time, as in  carrying  a weight  for a  long distance, and
also why a short  and violent  muscular action weakens and
tires us more than a protracted and more moderate one.  The
simple explanation is, that  but a part  of the fibrils are con-
tracted at once, and when the nervous  force is exhausted from
one set of fibrils, a new set are  called  into action to supply
their power.

   269. Examples of Muscular Strength.—As  examples of
great muscular strength, we have given to us the history of a
Samson and Goliath.  And  in more  modern times we read of
Milo of Crete who  killed an ox with his fist, and  then carried
it more than 600 feet.  He also saved  the life of his fellow-
scholars and teacher, Pythagoras, by  supporting  the falling
roof until  they had time to escape    Another  man is men-
tioned Avho could  raise 300  pounds by the muscles of his lower
jaw.  This strength, however,  is exhibited  much more strik-
ingly in another part of this chapter under the head of Com-
parative Myology.
 268. Do all the fibers, or even all portions of each fiber act at once in ordinary cases ?
Instance insane people.  269. Give examples of great.muscular strengh as illustrated by
Goliah and Milo. 
138
HITCHCOCK'S  ANATOMY
   270.  Rapidity of Muscular Contraction.—The  rapidity
of muscular movement i3 equally wonderful.   The pulsations
of the heart in children can often be counted as high as 200
per minute.   Some persons can pronounce  1500 letters in a
minute (of course combined in words), each one requiring the
contraction and relaxation of one  or more muscles, and both
occupying 3„Vu-th of a minute, or  ^Vth  of  a second.   The
muscles,   too,  which  move  the wings of some insects mus
contract  many thousands of times  every second in order to
produce the musical tone  or humming that is frequently heard
when their wings are in motion.
   271.  Duration of  Muscular Contraction—Intrinsic and
Available Force—Shortening of  Muscular  Fiber—Muscu-
lar Sense—Sound and  Heat.—The  length  of time  which
muscles may be on the stretch is  astonishing, but especially
so among:  the  lower  orders  of  animals soon to be mentioned
   The intrinsic force of a muscle is no measure of its  avail-
able power.   Thus the deltoid, if able to act in a perpendicu-
lar direction, would raise  1000  pounds; while, acting at the
great mechanical disadvantage (that it does) of passing over the
head of the humerus, it can not lift 50  pounds held in the
hand.
   The amount of shortening of the fiber in muscular contrac-
tion is differently stated  by physiologists.   The statements
are from  one  third to one sixth the  length  of the muscle.
That is,  a muscle three  inches long  can by contraction be-
come only two inches, or one six  inches long  become five
inches.   It is  probable, however, that the former statement is
the nearest to the truth, and that a muscle is shortened from
one half to one third its original length.
                          _        o
   The muscles give but little evidence of sensibility ; that is
perception of objects by pressure or touch; but when fatigued oi
overworked, they give a painful sensation, and also give to theii
 270. State  instances of great rapidity of muscular movement, as in pulsations ol
children's hearts and the power of articulating words. 271. State the distinction be
tween the intrinsic and available force of muscles.  How much does muscular flbe*
ihorten during its contraction ?  What is muscular sense ? 
AND  P II Y S I (> L Oilf.
139
possessor a very delicate sense of the amount of their contrac-
tions.
  It is also an established fact that a peculiar rumbling sound
is given off and heat  evolved during  muscular  contraction,
the latter of which  is  easily explained by the increased mus-
cular waste,  or the absorption of oxygen and evolution of car-
bonic acid.

  272.  Precision  of Muscular  Contraction.—An astonis!.-
mg precision in contraction  of muscles is seen in  those of the
human  larynx.  The  largest of these muscles  is less  than
three fourths of an  inch, and the total  amount of contraction
one  fifth.    And since the  ordinary compass of  the  human
voice is two  octaves, or twenty-four semi-tones, and ten inter-
vals between each of the contiguous semi-tones can be easily
detected by a person with a cultivated ear, there must  be  a
shortening of only yaVoth of an inch.   And  more wonderful
than all is the precision and readiness with which  an ordinary
singer can accurately strike one note after another with inter-
vals of from two to twenty-four  semi-tones.
                  HYGIENIC  INFERENCE.

   273.—1. Muscles need  Use.—The muscles should be used.
This is necessary to stimulate the blood-vessels and lymphatics
to a healthy action, so that  the  nutritious particles  may be
deposited in proper  proportion,  and the waste particles be re-
moved ;  in other  \\ ords, to promote  that  constant  change
which in all the organs of the body is so necessary for health,
Their moderate use also promotes  their growth and strength,
while inaction cauees them to diminish  both  in strength and
6ize.
 Speak of sound and hea'- attendant upon muscular contraction.  272. What remarkable
precision is there ir many muscular movements?  273. Why is it necessary that th«
muscles be used to » moderate extent ? 
l4o
HITCHCOCK'S   ANATOMY
  274,—2.  Muscles need  Rest.—The muscles also need rest.
That is, after work they need repose to restore the  energies
which  they have expended, and if the  amount of  rest which
they receive is  not sufficient to recruit the strength, they will
soon become small and weak ; for the lymphatics are so stimu-
lated that the amount of matter removed exceeds what is de-
posited.   But sleep is the grand restorative after severe mus-
c ilar exertion ; this alone  gives back  to the  muscle its life
and strength.
  275.-3. Muscles should Rest gradually  after  Violent
Exercise.—Experience,  however, shows that when the  mus-
cular system has been exercised vigorously it  should not be
allowed perfect rest at once, but by degrees.    Such a course
would save many an ache  and stiff joint to the hard-working
farmer  and mechanic,  and  especially to  the  one who labors
till the body is in a state of perspiration..
   276.—4.  Muscles  require Regular Exercise.—Labor or
exercise that is regular and uniform is much the most conducive
to health.   The muscles will endure a much greater  amount
of effort if made steadily, rather  than spasmodically.   Regu-
larity of action is  important in every  function, but in none
more evidently so than the muscles.
   277.—5. Especial want of  Exercise  by  Students and
Sedentary  People.—We see that students and other  seden-
tary persons are in special need of physical  exercise, and
should consider it a moral duty to secure  it, for it stimulates
every  organ  to a  healthy action.   The  blood  flows  more
  cadily, and more completely fills  all the  minute vessels;  the
  ianc1^ of the skin  act  more vigorously ;  the  lymphatics and
  aitritive vessels perform their part more perfectly; and even
    nervous system is kept in a healthy state by exercise.   It
is best, however, to  get exercise if possible with  some other

  274. For what do the muscles of hard-working men need rest, and especially sleep ?
275. Is it always best to gain rest at once, or gradually ?  276. What kind of labor or ex-
ercise is most conducive to health?  277. Vhydo students and sedentary people stand
greatly in need of muscular exertion ?  Is mere drudge work the best exercise ? 
AND  PHYSIOLOGY.
141
motive than a mere conviction of its necessity and importance.
For if we are interested in pursuing  an object, the mind ac-
quires a healthy action, and by its reaction brings on a state
of perspiration in the body.  In this case we  have obtained
two ends, the muscular system has  been  exercised,  and the
mind has gained full recreation from study.   Hence the study
te natural history, and especially those branches  of  it which
'i'quire  field  exercise  in   collecting  specimens, not  only
strengthens  the mind  and furnishes new objects  of thought?
but is an admirable method of gaining bodily strength.
   278.—6. Value of Gymnasia,  etc., to Colleges and Acad-
emies.—We see  how injurious to health  is the stimulating
plan adopted  in too many of our higher seminaries of learn-
ing.   The mind  is  crowded to its  utmost with  labor;  too
much time is taken  up with cultivating  the  intellect, while
the body  is  left  to take care  of  itself.   A  gymnasium  or
some  equivalent means  of  taking  exercise is  as important
a  thing to  our  colleges and  academies  as  are  the  build-
      er              o
ings,  libraries and  cabinets  themselves.   And may  it not
be the  reason why literary men are generally so great suf-
ferers from ill health, that so little attention is paid to physi-
cal culture  during  the preparatory and  collegiate  course ?
Is it not poor economy to take so much pains to cultivate the
inhabitant, when the house that it is to live in is such a mis-
erable tenement, and receives so little care  and improvement ?
 REMARKS  UPON  MUSCULAR  DEVELOPMENT.

  With the  existing customs  of  the   wealthier  classes  of
society, and our higher seminaiies of learning especially, it ia
hardly possible to say too much upon the necessity of physical
education : not that it is best to lower  the standard of intel-
 Why does the study of some branch of natural history secure the best exercise? 278.
What is said of the effect of a neglect of muscular exercise in schools and upo_ many
•ducated men of our country? 
142
HITCHCOCK'S  ANATOMY
lectual culture in the least, cr to dictate how those who are
possessed of an abundance of wealth shall dispose of it, but
simply to say that a thorough physical  education  is essential
for a proper enjoyment and improvement of our whole nature,
body, mind, and soul.   The evils of a neglect of this  branch
of education exhibit themselves, not only in puny clergymen
and lawyers, but in the meager and attenuated physiques  of
our mothers and sisters.
   Boys,  especially when  boys,  will  run,  jump,  shout, and
be  in  the  open  air  in  spite  of any thing  but  the  closest
watch ; in fact it is thought proper  that boys should be ruddy
in  countenance and  healthy,  but with girls  it  is not  so.
By grossly perverted usages of society, it  is  considered im-
proper for girls to run and jump and  shout, and especially so
out of doors; but while mere children even, they must act  as
young ladies, and never move except in a precise and meas-
ured manner,  often as unnatural as it is injurious; and any
thing that requires  muscular  effort,  is regarded  as vulgar,
and of course  not to be undertaken.    Now,  physiology tells
us  that  just  the  thing which our  girls  and ladies  stand
in need  of at  the present day is active, vigorous  muscular
effort,  such  as walking, rowing, riding on  horse-back, and
calisthenic and gymnastic  exercises.   And let the question
be  suggested  to  parents, guardians,  and  in fact all inter-
ested in  the prosperity or  even the existence of the Anglo-
Saxon race on  this continent, whether the  physical develop-
ment of  ladies shall be neglected through  the  idle whim  of
its  impropriety (which  often  only generates  a  false mod'
esty or  prudishness), and thus  tend to a  deterioration  of
the race  which is  now  in fearful progress  in the United
States.
  Without a  proper  exeroise  of  the  muscles  in man  or
woman, all the other portions  of the  body must suffer, and
if so, why, through an over sensitive, prudish caution, must
woman be the unfortunate  victim?    The  old  Greeks—
heathen though they were —did not neglect the development 
AND  PHYSIOLOGY.
143
of the body in either men or women.  And while they  most
thoroughly disciplined the intellectual  powers, their "semi-
nary of learning'' was the gymnasium, where, as prominent
characteristics, were the running, wrestling, and boxing exer-
cises, and by them regarded as equally important with intel-
lectual effort.
   But though the neglect  of muscular exercise  is  the  most
sadly evident in  the  female  portion of  society, yet it is not
confined here.  For  many of our educated men are of feeble
physical culture, mainly because of the cultivation of the in-
tellect at the expense of the body.   Most men in the academ-
ical  and professional schools are apt to regard study as first
and foremost, and a care of the body afterwards—?/ there be
any time for it!  How many make it a duty -and a relig-
ious one  too—to take all  the time that can possibly be se-
cured  for study, and leave  the  exercise as a thing desirable
but not essential!  But we maintain that a system of educa-
tion which  simply crowds  the mind  with discipline, to the
neglect of physical  culture, is  not only a defective, but a
monstrously  pernicious  system.    Students  may  bear the
cramming process through  the academical,  collegiate, and
even professional course, but sooner or  later the body will be
overpowered.  Nature's laws cannot be violated without suf-
fering the penalty at some time; and of what service can the
most cultivated minds become, if the body is too  feeble to use
their learning?   Of what beauty  is the  most brilliant gem
without  the °art of the  lapidary to develop and exhibit its
splendor ?
   In how few educational  institutions in our country is there
any thing like a system of exercise suggested, or much more
required?   In how  few of  them does muscular development
meet with any thing  but discouragement ?
   It is true  that muscular development has for too long a time
among us been associated  with the lower class of  people,  as
prize-fighters, shoulder-hitters,  bruisers and horse-racers,  in
all which cases it should meet a decided disapproval.  But  is
                             7 
144
HITCHCOCK'S  ANATOMY
this  a natural tendency  of physical  development ?   Is it
necesaary that a  well-developed  man  must of necessity be a
brutal fighter ? or that a beautiful horse must necessarily lead
his master to expose him to cruel excesses to test  his speed ?
If we do adopt the  principle  that  physical development has
such  an  immoral tendency, is there any culture of body or
mind that we  shall  not  be compelled to resign to the great
tempter,  since he can so sadly pervert every thing ?
   Ought not then a gymnasium or some equivalent means of
physical  culture,  to be attached to all our educational institu-
tions (female  as well as male), as well  as models, libraries,
cabinets, and apparatus ?   And if so, why should there not
be regular trainings of the body required by instructors as well
as mental exercises ?  And since but a small portion of time
is required for physical exercise if it be vigorous,  as it will of
necessity be in a gymnasium, why may not a portion of school
duties each day be a half hour or an hour  of exercise in the
gymnasium morning and evening ?   Does not every practical
teacher see that at least this would relieve the necessity of a
great many excuses, such  as for " head-ache," " feel sick,"
" unable to study to-day,"  etc.
  Fig. 153.    There  are, however, many simple gymnastic ex-
      1    ercises which may be indulged  in  by everybody,
          boys and girls, men and women,  without an outlay
          of any thing except a few dimes, and the  use of a
          few yards of space anywhere on terra firma.
             From a piece of inch pine board from two to four
          feet long (depending on the size  of the person to
          use it), and three to six inches wide, let an instru-
      i|    ment  be made called the back board,  as  is shown
      I    in Fig. 153.   With this simple piece of apparatus
           grasped  at each end,  as in Fig. 154,  a great  va-
riety of exercises can be  invented by any one, which will soon
set the whole surface in  perspiration,  and if persevered in
will, in the course of several days, impart pliancy and strength
to the muscles.
/ 
AND  PHYSIOLOGY.
145
      FlG- 154-          A more vigorous exercise can Fig. 155.
                     be obtained by using what  is
                     termed  the  " Indian club," or
                     " scepter," one in  each hand.
                     (See Fig. 155.)  These may be
                     made by the commonest turner
                     from any sort  of wood, and  it
                     is  well  that  there  be  several
                     pairs of them, differing in weight
                     and  length,  and loaded  with
                     lead if  necessary,  adapted to
                     the age  and muscular development  of
                     those using them.   And it is astonish-
                     ing what great strength of ymscle  can
                     be acquired  by this  means of exercise
                     continued through a few weeks.   Some
of the different exercises which may be performed with this
club may be  seen in Fig. 156, p. 146.
  Another simple mechanism  for gaining physical exercise,
called the '' triangle," is seen in Figs. 157 and  158.  It is
Fig. 158.
Fig. 157 
146
HITCHCOCK'S  ANATOMY
Fig. 156.
 
AND  PHYSIOLOGY.              HI
Fig. 159.
made by hanging a bar
between the ends of two
ropes twisted together,
as in Fig. 157, or from
two  ropes hanging per-
pendicularly from the
ceiling.    This triangle
may be suspended from
the ceiling of any room,
or the branch of a tree,
and is of great service
for  exercise,   since  it
calls into  use not only
the upper, but  also the lower extremities.
   But much more complete exercise, and that which tends to
give symmetry of form  to  either sex, may be obtained from 
148              HITCHCOCK'S   ANATOMY
Fig.  160.
 
AND   PHYSIOLOGY.                  149
Fig. 161.
 
150
HITCHCOCK'S  ANATOMY
the various  appurtenances of the  gymnasium.   Here,  by
means of bars, ladders, ropes and similar pieces of appara-
tus are the best arranged contrivances, not only for  a gen-
eral exercise of the whole body, but  for developing  the most
important muscles.   A few  pieces of  this kind  of furni-
ture  may be  seen in  Figures 159, 160, and 161.   These
may  be  fitted up in any lar e  and  unfurnished  building.
since  the essential  requisites are  a  few solid  timbers  to
give firm support to the bars and ladders, and  walls  mainly
to protect from exposure to severity of weather.
   The exercise of rowing is one which probably can  not be
surpassed as a means of exercise, since it not only requires a
use of the muscles, but is exhilarating  and recreating  to the
spirits; and where circumstances admit, whether as  supple-
mentary  to or in place of a gymnasium, we would say by ail
means let both boys and men, and  ladies too, indulge  in the
invigorating and healthful exercise of boat rowing.
             COMPARATIVE  MYOLOGY.

  279.  In microscopic  structure the  muscles of the lower
orders of animals very closely resemble those of man, as may
be seen in the fibrils of the pig, Fig. 162.

  280.  Tegumentary  Muscle—Abdominal  Muscles—Mus-
cles  of  Lower  Jaw—Diaphragm—The general structure
and relations of the  muscles in  quadrupeds  differ very little
from those of man save in the extremities.   Nearly all quad-
rupeds have a set  of fibers  called the  Tegumentary Mus.
cle, which is a thin  layer of muscle  lying just beneath  the
skin,  and which is  only rudimentary in man.   Its func-
tion is to contract and corrugate the skin in order  to remove
dust, insects, or any offending matter, as can be seen in a
  279. What is said of the structure of muscles in all mammals ?  280. Describe tho
Tegumentary Muscle. 
AND  PHYSIOLOGY.
151
                     b  a
 Muscular Fibrils of the Pig. a, An ap-
parently single fibril, b c, Collections of
fibrils.
horse or cow during the time              FlG- 162-
when flies  irritate  by biting.
The same muscle in the por-
cupine and armadillo is made
use of to roll themselves up in
a ball.   In apes the foot  and
hand are similar both in mus-
cular development  and func-
tion, but  are  by  no  means
equal  to the  hand of man.
The abdominal muscles of all
quadrupeds are stronger than
man's, since from  their posi-
tion the weight of  the  viscera
is thrown upon the muscular
walls  of  the  abdomen,  and
not upon  the bones  of the pelvis, as in  him.   In beasts of
prey the masseter  and temporal muscles  are more strongly
developed  than in man,  because  great  strength is required
in the jaw to secure the food  and fit it  for digestion.   In all
mammals a more or less complete diaphragm is found, though
it is absent in nearly all the remaining vertebrata.

    281.  Muscles  of  Birds—Ossification of  Tendons—The
 muscles of most birds  are remarkable for their deep red color
 and the density of  their structure.   In herbivorous  ones, how-
 ever, they are of a paler color and softer in texture, and hence
 more palatable as articles of food.   The bellies of the muscles
 are for the most part situated on the body, so  that  they may
 not encumber the limbs ;  and  those designed  to move the ex-
 tremities  are extended into  long tendons, which,  as already
 mentioned, become ossified to a considerable extent.
 Of what use is this muscle in the porcupine and armadillo? Why are the abdominal
muscles of quadrupeds proportionally stronger than in man? What is said of the strength
of the masseter and temporal muscles of beasts of prey?  What of a diaphr"gm? 2S1.
What are the muscles of birds remarkable for ?  What is said of the tendons »nd  bellies
•f muscles in birds ? 
152
HITCHCOCK'S  ANATOMY
   282. Suspensory  M n s c 1 e.—In the turkey and birds of like
character an especial muscle  is  provided for the support of
the crop,  which so often becomes heavily loaded  with food.
   283. Muscles  of  Birds'  Feathers —Their   Use — Their
dumber—Muscles of the Breast.—Birds  are supplied with
tegumentary muscles somewhat after the manner of quadru-
peds.   The main  difference  is,  that in birds a  few muscular
fibers are sent to each quill feather of the body,  by which the
feathers can be  violently shaken to dislodge dirt, or they may
be merely raised on end by the same muscles.  This property
is well  seen in  common barn fowls, when they shake them-
selves after having lain  in dry dirt.   A hen with a  brood of
chickens,  too, when disturbed shows her wish to protect her
young by ruffling up her feathers and attacking  whoever may
annoy her.   In some birds, where there are 3,000 quill feath-
ers, the number of muscles  must  be at least 12,000.   No
muscles are found upon  the  face  of  birds, but  to secure  the
degree of motion to which the head is subject, and the flexi-
bility of the neck,  the muscles of this portion of the body are
Very strongly developed.  The  most  powerful muscles  of
birds are the pectoral,  or those  on the  breast; one end  of
which is attached to the keel  of  the sternum and the other to
the humerus.   These muscles are three  in  number on  each
side, and the largest one exceeds in weight all the other mus-
cles of the body.
  284.  Muscles of Fishes.—The muscles of fishes are char-
acterized  by their  slight degree  of separation from one an-
other, by the absence of long tendons, and the softness of their
fibers.   Their color  is  generally white,  or  yellowish white,
but in microscopic structure they do not differ  from  those  of
the other vertebrata.   By far the largest part of the fleshy

  2S2. What peculiar muscle is found in birds like the turkey ?  283.  What is worthy of
note in the tegumentary muscle of birds?  In what condition does a hen show the ac-
tion of the tegumentary muscles?  What number are there in some birds? Why is
there need of so few muscles on the head of birds?  Upon what portion of tho body are
there the most muscles?  Give the actual amount by weight. 284. What is the peculiar
feature of the muscle of fishes ?  Give their coloc 
AND  PHYSIOLOGY.
153
mass  of these animals is made up  of the  lateral muscles of
the body which extend from the head to  the  caudal fin ;  and
as each lateral muscle by its contraction bends the body to its
own side, the motion of the fish through  the water is effected
in the same manner as the oarsman sculls his boat.
                          Fig. 163.
M_s«ular Fiber from Leg of Meat Fly. a, Termination of Muscular Fiber,  t, Tendon.
  285.  Museles  and  Locomotive  Organs of the  Inverte-
brates.—Muscles,  both striated  and smooth, voluntary  and
organic, abound in all the invertebrates.  They are modified
in form and position to meet the wants of the animal as wisely
as in the higher tribes.
In some of  the Polypi
movements are made by
the contraction of their
sides, in which no mus-
cular fibres have been
discovered,  though ex-
existing in  other parts
of  the animal.    The     Insect Fasciculi Magnified Fifty Diameters.
muscles of insects are either colorless or of a dirty yellow.
  286. A great variety of locomotive organs are found in the
Invertebrates.   The Echinoderms have tentacles, called Am-
bulacra, on some of which there are  suckers, which enable'
them to hold  on to  substances.  They have  also forcep-like
organs of locomotion.   Most of the acephalous molluscs move
by  a highly developed foot, which, in the Cephalopoda, is used
as a sucker.   The Cephalopods  have  arms with suckers at-
  What portion of the body is made up of them?  286.  What are the locomotive organ*
of Invertebrates?
 
154           HITCHCOCK'S  ANATOMY.

tached to  the  cephalic cartilage.   Annelids  move  by sub-
cutaneous muscles, stings, and bristles.   The  Rotatoria  re-
volve by a retractile vibratile apparatus.   Crustaceans have
usually two legs to each segment, and the Myriapods some-
times four.   Some of these appendages are tactile, some for
oars, and some  ambulatory.   Spiders have four pairs of legs,
and insects three.
   287. Examples of  Muscular  Strength.—There are some
remarkable examples of muscular strength among the lower
animals.   A flea harnessed will draw from seventy to  eighty
times  its  own  weight, while a horse  can  not draw more than
six times his weight.  The flea weighs less than a grain, and
will clear  several feet at a  leap.  The  common dorr bettle,
weighing but fifteen grains, has been known to heave a weight
placed upon him  amounting to 4.769 grains, equal to nearly
320 times his own weight.
   288. Length  of Time the Muscles  can  be Employed,
 —The length of time during which some muscles can be em-
ployed without rest is also very remarkable.  Many birds will
fly uninterruptedly for hundreds of miles, and it is also said
that insects  will  remain  suspended in the air a whole sum-
 mer's day without alighting.
   289. Rate  of  Flight  of  Birds.—Some  birds  fly sixty
 feet in a second;  but a race-horse scarcely ever exceeds forty
feet in the  same  time.   A falcon of King Henry II.  flew on
one day  from  Fontainbleau  to  Malta,  a distance  of about
1 000 miles.  The rice-bird, which afterwards becomes the
reed-bird of Delaware Bay and the bobolink of New York, is
often  found below Philadelphia with  green  rice in its crop.
 The same thing  is true of  pigeons  during the rice-growing
season.
  287. State the power of a flea compared with a horse. 288. What is wonderful abont
the length of time that some insects can use their muscles without weariness?  289. With
what speed can some birds fly ? Give the iustance of King Henry's falcon. 
             CHAPTER  THIRD.

THE NUTRITIVE SYSTEM.—SPLANCHNOLOGY, OR HISTOR-
             OF THE DIGESTIVE ORGANS.
        DEFINITIONS  AND  DESCRIPTIONS.

  290.  Definition of  Digestive Organs.—The Digestive Orj
gans are those which receive the food into the body and effect
such changes in  it that the various tissues can be formed
from it by means of the glands.  Of these organs the princi-
pal one  is the Alimentary Canal.  This  commences with the
mouth, and includes the stomach, with the whole  length  of
tube known as the intestines.   This canal, in a full-grown
man is about thirty feet in  length, being as a general rule
five times the height of the  individual, and  is lined through-
put its entire length by mucous membrane.

   291.  The  Mouth;  Salivary  Glands;  the Tonsils.—The
Mouth contains the organs of mastication including the teeth
and tongue, and receives the saliva, which is secreted by three
pairs of glands named  Parotid, Submaxillary, and Sublingual,
situated just beneath  and behind the lower jaw.   Besides
these three glands there are many other minute  glands and
follicles situated  upon the floor and backsides  of the mouth,
which  secrete  fluids that aid  in  mastication  and digestion.
The Tonsils are simply an aggregation of follicles situated in

  290. What are Digestive Organs? Give  the general description of the Alimentary
Canal.  291. What does the mouth contain ?  Name the three  principal pairs of glands
and give their location. 
156
HITCHCOCK'S  ANATOMY

            Fig. 165.
  A View of the Salivary Glands in situ. 1, The Parotid Oland in situ and extend-
ing from the Zygoma above to the Angle of the Jaw below.  2, The Duct of Steno.
3, The Sub-Maxillary Gland.  4, Its Duct.  5, Sub-Lingual Gland.
Fig. 166.
                                        the upper part  of the
                                        fauces  or throat,  a few
                                        of  which are represent-
                                        ed  in  Fig. 166.    The
                                        mouth  is a variable cav-
                                        ity  having  no  empty
                                        space   within  it  when
                                        closed,  and when  fully
                                        open, containing nearly
                                        half a pint.

                                          292. The Pharynx.—
                                        The Pharynx (the Greek
                                        name for this portion of
the body) is the next division of the  alimentary canal.   It is
a  short and somewhat irregular  tubular cavity, into  which
the mouth  opens  behind, serving  as   a  portion  of  the  canal
A fow Follicles from Human Tonsil.
 What are the Tonsils?  Are there any other glands in the mouth?  292. Describe the
Pharynx. 
AND  PHYSIOLOGY.
157
         Fig. 167.
Pendulous Palate.
Baf_ of the Cranium.
Pharynx.
Esophagus.
Nose.
Torjgue.


Salivary Glands.

Lingual Bone.

Larynx.


Thyroid Gland.
Trachea or Windpipe.
Vertical Section of the Mouth and Throat.
fr-rn the mouth to the stomach, its  lower limit being nearly
opposite to the Pomum Adami (Adam's apple) in front, and
the fifth cervical vertebra behind.  It also communicates with
both ears,  with the nostrils and lungs, by passages which open
directly into it.   The communication between this cavity and
the mouth may be  entirely cut off by means  of a  movable
muscular curtain called the soft or pendulous palate,  which is
of great service in the act of SAvallowing.   This  portion of the
alimentary canal  is made up of muscular fibers which run  in
two directions, so as to cross each  other  at  a large  angle,  in
order to give the most  perfect compression  upon  the food  as
it passes through it.   And  in its lining (mucous) membrane
are found  a  great  number  of follicles or sac-like bodies  of
microscopic size called Pharyngeal Glands.
  293.  Esophasrus.—The  Pharynx terminates in  the  Eso-
phagus  (meaning  the passage  for conveying the food).   This
 What cavities does it commuuicate with?  What is said of its muscular coat? 293
What is the Esophagus ? 
IT) 8
HITCHCOCK'S   ANATOMY
Pig. 168.
Glands of Esophagus Magnified fifteen Times.
is a long and narrow tube, made  up  of two  muscular coats,
which terminates in the stomach by the cardiac orifice.   It is
smaller  in size than the Pharynx, and contains a great, num-
ber of minute glands, (see Fig.  168),  which secrete  an oily
fluid  when  the food is passing through it.
  294.  Stomach, its  Coats,  its  Size,  its  muscular  Coat,
                            Fig. 169.
  Section of Human Stomach.  1, Esophagus.  2, Cardiac Orifice.  3, 4, 5, 6, Greater
and Lesser Curves of the Stomach.  7, Dilalation, or rudiment of a Second Stomach.
S. Folds of the Mucous Membrane.  9, Pyloric Orifice.  10, 11, ana H, Duodenum.
12, Duct of Pancreas and Liver.  15,  Jejunum. 
AND  PHYSIOLOGY.
159
Gastric Follicles.—The Stomach is the largest expansion  of
the alimentary  canal,  situated  in  the  upper portion  of the
left side of the abdomen,  immediate'y beneath the diaphragm,
inclining obliquely downwards from the left to the right.   Its
walls are made up of three coats: an outer or  serous, a middle
or muscular, and an inner or mucous.   Its normal or average
size will allow it to contain  about  a solid  quart,  but in  gor-
mandizers, and wine and  beer drinkers, it  is  dilated to  threa
or four times that size.   In the middle or muscular coat (Fig.
170)  the fibers run at right angles  to each other, in order that
                            Fig. 170.
  A Front View of the Stomach, distended by flatus, with the Peritoneal Coat turned
off. 1, Anterior Face of the  Ksophagus.   2, The Cul-de-Sac, or greater Extremity.
3, The lesser or Pyloric Extremity. 4, The Duodenum.  5, 5, A portion of tue Peri-
toneal Coat turned back. 6, A portion of the Longitudinal Fibers of tho Muscular Coat.
7. The Circular Fibers of the Muscular Coat.  8, The Oblique Muscular Fibers, or
Muscle of Gavard.  9, A portion of the Muscular Coat of the Duodenum, where its Pe-
ritoneal Coat has been removed.

they may contract  in the most efficient manner upon the  con-

tents of the stomach for the  purpose of digestion, and forcing

the contents  onwards  into the Duodenum.  They also assist

in forcing the contents of the stomach backward in vomiting.

In the inner or  mucous lining are situated an  immense num-

  294. Where is the Stomach situated?  What is its normal size?  How many coats has
it and what are they?  Of what service is the  muscular coat?  What glands are con-
tained in the mucous membrane of the stomach ? 
160
HITCHCOCK'S  ANATOMY
ber of tubular glands which open directly  into  the stomach.
They are cup-shaped cavities about the 33Voth 0I* an mcn i°
diameter, and 7V;tli  in length,  from the bottom of which pro-
ject two or more parallel  tubes,  ending  in  a closed  termina-
tion in the tissue beneath.   These compose the greater por-
               Fig.  171.                       Fig. 172.
 Diagram of the Stomach and Intestines. 1, Stomach.
2, Esophagus.  3 and 4, Stomach. 5 and 6, Duode-
num.  7, Jejunum.  8, Ileum.  9, Csecum. 10, Ver-
miform Appendix. 11,12, 13, 14, Colon. 15, Rectum.
 The Glands in the Coats of the
Stomach, magnified forty-five dia-
meters. 1, A Gastric Gland, from
the middle of the Stomach. 2, An-
other, of more complex structure,
and appearing to contain  Mucus
—from  the neighborhood  of the
Pylorus.
tion of the mucous mem-
brane, and are  for the
purpose of secreting the
gastric  juice, and prob-
ably the Pepsin  also. In
addition to these glands,
a  large  number of the
mouths  of  veins  open
into the stomach, which
act the part of absorbent
vessels   to  remove tha
water, whether  pure cr
mixed with  other sub-
stances.
    295.  Duodenum.—
The first division of the
Intestines  is the  Duo- 
A.SD  PHYSIOLOGY.
161
denum, because in length it is equal  to the breadth of  twelve
fingers.   It commences with the pyloric  orifice  on the right
extremity of the stomach,  and runs  slightly  backwards and
upwards  until  it  terminates  in the  Jejunum.   It  is often
called the second stomach, because  a  certain part of digestion
takes  place  here, and the  food  passes slowly  and receives no
less than three different secretions : one  from  the  Liver, an-
other  from  the  Pancreas,  and  the  third  from  the  Mucous
membrane of the intestine itself.
   296. Jejunum.—'Next below the Duodenum is the Jeju-
num, meaning "empty," since it is always found in this con-
dition after death.   This, like the other divisions of the intes-
tine,  has  three coats, and is  of a slightly pinkish color,  be-
cause here the mucous membrane is  thicker than in any other
of the intestines.
Fig. 173.
   297.  Ileum___The  Ileum
(from the  Greek  signifying
to twist) is the third division
of the Intestines, and is about
fifteen feet in length.   It is
the smallest Intestine, and has
a darker color than either of
those already mentioned, and
is exceedingly tortuous in its
course.
   298.  C a; cum .—The fourth
division  of the   Intestine  is
the Caecum.    This is a shut
sac  much  larger  than  the
small  Intestine,  and  of  a
  The Caecum and its Appendix.  1, C_
cum.  2, Colon  3, Ileum.  4, Entrance
from Ileum to Colon. 5, Ilio-Caecal Valve.
6, 7, 9, Parts of the Appendix Caeci.
  What do they secrete ?  What vessels open into the stomach, and of what service are
they? 295. What is the Duodenum?  Give its general course.  Why is it sometimes
called the second stomach?  What fluids are  poured into it? 296.  What is the name
Jejunum derived from?  What is its color?  297. How long is the Ileum?  What ii
said of its shape ?  29S. Name the fourth divison of the intestines.  Describe it. 
162
HITCHCOCK'S  ANATOMY
grayish blue color,  and not exceeding three inches in length.
The entrance  of the Ilium  into the Caecum is effected by  a
valvular arrangement which allows the food to  pass into the
Caecum, but never in the opposite  direction.   It is situated at
the right  lnnominatum in the lower part of the abdomen, and
its lowest portion has a worm-shaped  process  attached  to it,
which is  only  rudimentary,  and  consequently of no  great
service to man,  but  largely developed and  of great service in
some of the lower animals,  and especially in the herbivorous
ones.
   299. Colon.—The Colon (from the Greek  signifying  "to
prohibit," since the food  passes very slowly through this part
of the  canal), commences at the  Caecum on the right side of
the abdomen,  and in the  first  part  of its course passes in an
upward direction, and  is called the ascending Colon.   When
it reaches the lower edge  of the liver, it crosses horizontally
to the extreme  left  edge  of the body, constituting the trans-
verse Colon.  After this  it descends,  and joins the  Rectum,
forming the descending   Colon.   Its  length is from five to
eight feet.
   300. Rectum.—The Rectum completes the divisions of the
Intestines.  It  is nearly  straight in  its course, of  a larger
size than  any other  division of the canal, except the stomach,
and from six  to eight inches in length.  Its name is derived
from the straight direction which it assumes.
   301. Division  of  the Intestines into small  and  large.—
The last  three  divisions  have  a. much larger  diameter  than
the first three, and are called on that account the large Intes-
tine, and  the  Duodenum, Jejunum and Ilium,  the small In-
testine.   The  latter seems to be the portion necessary for
preparing the food  to enter the Lacteals,  while the large In-
testines act mainly as a receptacle for  the waste portion.

  Where is its location in the body ?  What curious appendage is attached to it? 299.
What are the three divisions of the Colon?  How long is it?  300. What does the Colon
terminate in ?  How long is the Rectum ?  301. Define the large and the small Intestine.
and give their probable uses. 
A NT I)  PHYSIOL O (J Y .
163
              Fig. 174.
Liver. Pylorus. Gullet. Pancreas
   \     \       1     <
Gall-Bladder.
Large Intestine.
      Caecum.—.
Appendix of the _
      Caecum.
Stomach.
Spleen.
Colon.
Small Intestine.
Colon.
             Small Intestine.         Rectum.
                   Digestive Apparatus in Man.
   302. Structure  of  Intestines, Intestinal Glands.—Like
the Stomach, the Intestines are  formed  by three membranes.
Also  m the inner or mucous membrane are situated  an im-
mense number of microscopic glands, so that a French teacher
speaks  of  them  existing  •' as  numerous as  the stars  in the
starry heavens." They are distinguished as Duodenal Glands,
Brunners Glands, Solitary  Glands,  Peyer's  Patches,  and
Follicles  of Lieberkuhn.   (Fig. 175,  p.  164.)   They  are
most  abundant along  the course of the Ileum and  they seem
to be  especially affected in  Typhoid Fever, although  no  cer-
tain use for them in health  has as yet been  discovered.   The
 302. What is the structure of the Alimentary Tube ? What is said of the Glands found
In its mucous lining? State their Barnes. 
164
HITCHCOCK'S  ANATOMY
                                         Follicles of Lieberkuhn
                                         are found  only  in the
                                         large  intestine.    The
                                         Mucous  membrane  of
                                         this  part of  the canal,
                                         is  not smooth and con-
                                         tinuous with  the serous
                                         or outer layer,  but  is
                                         doubled upon itself in a
                                         great number of folds,
                                         in order that the surface
                                         containing these  glands
                                         may be the largest that
                                         is  possible, so that the
                                         contents of the Intestine
                                         may  receive a  large
supply from these secretions.   Minute Villi or  hair-like  pro-
jections are also  found  in great  abundance upon this mem-
              Fig. 176.                            Fig.  171.
  A Portion of the Ilium highly magnified, show
ing Peyer's Patches and the Vilii.
 A Portion of one of Brunner's Glands.       A View of a Longitudinal Section of th«
                                  Jejunum, showing the Villi as seen under
               the Microscope. 1,1, The Terminal Orifices of the Villi.  2, 2, The
               Internal Coats of the Intestine.  3, The Peritoneal Coat.

  How is the Mucous membrane arranged through the canal, and what is the design of
such an arrangement? 
AND  PHYSIOLOGY.
ion
brane, in order to increase the amount of its secretory surface.
It is the presence of villi that gives to some parts of the mu-
cous  membrane a velvet-like appearance,  and  in  these  villi
are found the  commencement  of  the lacteals, one  lacteal
usually being found in each villus.
   303.  Glands  attached  to  the  Intestines. — Connected
with the Alimentary Canal are  several large glands, a few of
which have already been described.  They  are  soft solids, of
various forms and sizes,  and are composed  of lobules or small
divisions, each  one of which is supplied with an artery, vein,
and duct.  Each of these ducts communicates with the prin-
cipal duct or outlet, which conveys  away  the  product sepa-
rated  from the blood  by  the  whole  gland.  In microscopic
structure, a gland  is  made up of very minute cells, which
seem to have the power of secreting  or separating from the
blood the particular substance which it is the function of the
gland to eliminate.
   304.  The Liver,  Gall-Bladder.—First  in  importance  of
this  class is the  Liver.  (Fig. 178, p. 166.)  This,  except-
ing the  brain, is the largest organ in the body, and is situated
on the right side of  the abdomen,  corresponding to the stom-
ach on the left, and is of a reddish yellow color.  The average
weight of it is four pounds, measuring twelve inches in its
longest diameter, and it is divided into five lobes or great divis-
ions,  and these  are entirely  composed of  minute bodies or
lobules, (Fig. 179, p. 166), which are about the size  of millet
seeds, each one containing an artery, a vein,  and a plexus, or
net-work of ducts for conveying away  the bile.   These differ-
ent plexuses unite with each other and form two hepatic ducts
 which discharge the bile into the Gall Cyst or bladder.  (Fig.
180, p. 167.)   This  is a pear-shaped sac, containing  from
one to two ounces,  of a greenish yellow color, situated under
  Describe the Villi. 303. What is said of the large glands connected with the organs of
digestion? State the structure of a gland.   304. What is the relative size of the Liver?
Where is it located? State its  color and weight. Give its minute structure.  What is
the Gall Cyst or Bladder?  What is the duct that carries the Bile to the Gall Cyst, and
the one that empties the Gall Cyst into the  Duodenum ? 
166
HITCHCOCK'S   ANATOMY
Fig. 178.
  The Inferior or Concave Surface of the Liver, showing  its Subdivisions into Lobes.
I, Center of the Right Lobe.  2, Center of the  Left Lobe.   3, Its Anterior, Inferior, oi
Thin Margin.  4, Its Posterior, Thick or Diaphragmatic Portion.  5, The Right Extrem-
ity.  6, The Left Extremity.  7, The Notch on the Anterior Margin.   8, The Umbilical
or Longitudinal Fissure.  9, The Round Ligament or remains of the Umbilical Vei'i.
10, The Portion of the Suspensory Ligament in connection  with the Round Ligament.
11, Pons nepatis, or Band  of Liver across the Umbilical  Fissure.  12, Posterior End ol
Longitudinal Fissure.  13, 14,  Attachment  of the Obliterated Ductus Venosus to the
Ascending Vena Cava.  15, Transverse Fissure.  1G, Section of the Hepatic Duct.  17,
Hepatic Artery.  IS,  Its Branches.  19, Ycna Portarum.   20, Its Sinus, or Division into
Right and Left Branches.  21, Fibrous remains of the Ductus Venosus.  22, Gall-Blad-
der.  23,  Its Neck.  24, Lobulus Quartus  25, Lobulus Spigelii.  26, Lobulus Caudatus.
27, Inferior Vena Cava.  28,  Curvature of Liver  to fit the  Ascending Colon.   29,  De
pression to fit the Right Kidney.   30, Upper portion  of its Right  Concave Surface over
the Renal Capsule.  31, Portion of Liver uncovered by  the Peritoneum.  82, Inferior
Edge of the Coronary Ligament in  the  Liver.   S3, Depression made by the Vertebral
Column.
Transverse Section of a Lobule of the Human Liver.    m   It J    IS   anOtDCr 
AND   PHYSIOLOGY.
167
Fig  180.
   A View of the Gail-Bladder distended with Air, and  with its Vessels Injected.
 1, Cystic Artery.  2, The Branches of it which supply the Peritoneal Coat of the
 Liver.  3, The Branch of the Hepatic Artery which goes to the Gall-Bladder.  4,
 The Lymphatics of the Gall-Bladder.
gland,  lying directly behind  the stomach.   It  is about  six
inches  in  length,  the right end  of  it  being somewhat  larger
than the left extremity, and  hence  called  the  head.   To  the
naked eye the lobular structure is apparent:  but each lobule
is  itself made  up  of much smaller  lobules.   The duct of  the
Pancreas  conveys the milk-like secretion of  this gland, to
nearly  the same point on the Duodenum as the Hepatic Duct,
where they both enter that tube in a slanting manner, so that
by the valvular arrangement the contents  of the intestine  can
not be  forced backwards into the Biliary or Pancreatic duct.
                              Fig. 181.
   An Anterior View of the Pancreas, Spleen and Duodenum, with their Blood Ves-
 sels Injected.  1, The Spleen.  2, Its Diaphragmatic Extremity.  3,  Its Inferior
 Portion. 4, The Fissure for its Vessels.  5, The Pancreas.  6, Its Head, or the
 Lesser  Pancreas.. 7, Duodenum. 8, Coronary  Arteries  of the Stomach.  9, The
 Hepatic Artery.  10, The Splenic Artery.  11, The Splenic Vein.

 305. Describe the Pancreas.  What is its structure ?  Where does its duct empty, *nd
what mechanical structure in it makes it remarkable ?
                              8 
ma
HITCHCOCK'S  ANATOMY
Fig. 182.
                                         306. Peritoneum.—
                                      The Peritoneum,  "cov-
                                      ering about," or exter-
                                      nal coat  of the  intes-
                                      tines is not a  little pe-
                                      culiar  in  its conforma-
                                      tion.    This,   like   all
                                      serous membranes, first
                                      completely  invests  the
                                      organs and  then  is re-
                                      flected from them so as
                                      to make a lining for the
                                      whole  cavity.    Hence
                                      the cavity  of  the  ab-
                                      domen, although a per-
                                      fectly  shut  sac,  is  of
                                      very  irregular outline.
                                      That it is  a  shut sac
                                      may be seen  from the
                                      fact that in dropsy  of
                                      the abdomen—the fluid
                                      has no means  of escape
                                      except by absorption, or
                                      puncture  from the out-
                                      side.    In  the  disease
                                      commonly known as  in-
                                      flammation of the bow-
els, this membrane is the principal  seat of the difficulty, and
the inflammation  of this  as well as of all other serous mem-
branes, is attended with acute pain, and the progress of tho
disease, for better or worse, very rapid.
   307. The Mesentery and tne Omentum.—These are folds
of the Peritoneum, attached to different parts of the abdomen
and its viscera, which serve  to  retain  some  of the organs in
 SOS. What is the Peritoneum ?  Is the cavity of the  abdomen of a regular outline ?
What is the principal seat of disease in inflammation of the bowels ?  307. What is tha
Mesentery and tha Omentum'? What is it thickly packed with ?
  Reflexions of the Peritoneum.  D. Diaphragm.
S. Stomach.  C. Colon.  _>. Duodenum. P. Pan-
creas. I. Small Intestine. R. Rectum.  B. Blad-
der.   The numbers indicate the course of the
Peritoneum. 
A.ND  PHYSIOLOGY.
109
their positions, and also, from the amount of fat contained in
them,  to  protect the intestines  from  cold and  mechanical
violence, and to furnish a soft surface for them to glide over
in their various  movements.  In a lateral view of the abdo-
men, Fig. 182, some of the  parts of the Omentum and Me-
sentery may be seen.  At  4 is seen what is known as the
lesser  Omentum, connecting the Liver and the Stomach.   At
5  and  6 are  seen the folds  which  constitute the  greater
Omentum.   At  10 is found the Mesentery,  which encircles
the small intestines.   This is a broad fold  of  the  Peritoneum
connected to the  middle of the cylinder of the  Jejunum and
Ileum  through  their whole length, and  is  attached to the
posterior wall of the abdomen.   Within the layers of the Me-
sentery are found from  130 to  150 bodies of almond shape
and size, known as  the Mesenteric Glands.   Through these
the Lacteals pass on their way to form the Thoracic Duct.
   308. Lacteals.—The Lacteals  are minute vessels, which
commence with  the  inner  or mucous coat of the intestines,
                         Fig. 183.
         Aorta. Thoracic Canal. Lymphatic Glands.
  (Radicles of the
... <  C'fcyhferoua
  I  Vessels.
-.....Intestine.
Lacteals. Mescnt.-ry.
       Chyliferous Vessels.
What small bodies are fouad la it, and what is tho use ol the Mesentery v 
170
II I'l'CHCO C K ' S   A X A T () M Y
Fig. 184.
and terminate in the Thoracic
Duct.   These  at their  com-
mencement  are  about   the
same  in  anatomy  with   the
radicles  or small veins,  and
at this point  act the part of
absorbents.   Soon after they
have left the  Intestines,  sev-
eral of  them  unite  into one
and pass through small bodies
of  about  the  size   of  peas,
called the Mesenteric Glands.
As  they  emerge  from these
glands,   they   are  fewer  in
number  but  larger   in   size,
until  they all  unite  into one
tube called the Thoracic Duct,
a  little   larger  than  a goose
quill,  at  about the  point  of
the   last  Dorsal   Vertebra.
This  vessel  passes   immedi-
ately  upwards,  lying closely
upon  the  Spinal   Column,
sometimes separating into two
smaller tubes for a few inches,
  A View of the Course and Termination of the Thoracic Duct.  1, Arch of the Aorta.
2, Thoracic Aorta.  3, Abdominal Aorta.  4, Arteria Innominata.  5, Left Carotid.  6,
Left Sub-Clavian.  7, Superior Cava.  8, The two Venae Innominatse. 9, The Internal
Jugular and Sub-Clavian Vein at each side.  10, The Vena Azygos.  11,  The Termina-
tion of the Vetia Hemi-Azygos in the Vena Azygos. 12, The Receptaculum Chyli: sev-
eral Lymphatic Trunks are seen opening into it.  13, The Thoracic Duct dividing, op-
posite the Middle Dorsal  Vertebra, into two branches, which soon re-unite; the course
of the Duct behind  the Arch of the Aorta and Left Sub-Clavian  Aorta is shown by t
Dotted Line. 14, The Duct making its turn at the Root of the Neck  and receiving sev-
eral Lymphatic Trunks previous to terminating in the Posterior Angle of the Junction
of the Internal Jugular  and  Sub-Clavian Veins.  15, The Termination of the Trunk o!
the Lymphatics of the Upper  Extremity.
  308. Where do the Lacteals begin, and where do they terminate?  What do they re-
semble, and what do they pass through ? State the size of the Thoracic Duct, its course
and termination. 
AND  PHYSIOLOGY.
171
until  it  reaches  a point as high  as  the clavicle,  where  it
gradually curves  forward, and joins  itself to the  left sub-
clavian vein.  The Lacteals and  Thoracic Duct  are all made
up  of three coats and present  a  silvery white appearance
from the color  of the  fluid they contain.  Their function  is
to convey the Chyle or nutrient  portion of the  food  into the
blood.
   309.  Kidneys.—The Kidneys are two in number, situated
upon the side of the  lumbar vertebras, and are generally en-
closed in a large amount  of fat.   Their average size is be-
tween four  and five inches in length, two and a half inches  in
breadth, and  one in thickness.  Their color is  of a reddish
yellow, and form decidedly oval, with a depression in one of
the sides.   Upon its upper extremity is  a small body, called
the  Renal  Capsule, and the whole organ is abundantly sup-
plied with blood.   The design of it seems to be the removal
Fig. 185.                     Fl»- 186-
 
172            HITCHCOCK'S  ANATOMY

of the waste Nitrogen of the system, and many salts, espe-
cially the Phosphates, which can be eliminated by no other
organ.   The secretion  of  the  kidneys  is  the  urine, upon
the regular secretion of which the health of the system greatly
depends.
     FUNCTIONS   OF  THE  DIGESTIVE  ORGANS.

   310.  mastication;  Use of the Tongue;  Use of the Saliva,
Amount  of Saliva.—The first process through which the food
must pass is Mastication, or  reducing it to a pulp by means of
the teeth and admixture of the saliva.  The service of the tongue
is  to keep the food between the teeth and to place it in such a
position that it will  readily receive the saliva.   The saliva is
of use to moisten the food, since the gastric  fluid will much
more readily dissolve it than if dry or solid.   It aids articu-
lation and the  sense  of taste by keeping  the  lining of the
mouth in a moist and  pliant state. It also is of use to  cleanse
the mucous membrane, and  by its moisture to quench  or pre-
vent thirst.   Air is also carried  by it  into the stomach to aid
the process of digestion.   But the most important use of this
fluid is the conversion of starch into  sugar.    This property
depends  mainly upon a peculiar  organic active  substance con-
tained in it called Ptyalin, and is most active when  in a state
of incipient decomposition.  The saliva secreted daily varies,
according to different  authorities, from about three pounds to
six pounds and a half, and is alkaline in its character.   Acid,
aromatic, and pungent substances increase the  amount of the
secretion very much.

   311.  Deglutition.  A  part of the   Process   involuntaiy1
—After  mastication,  the next  process is  that of  swallow-
ing,  or deglutition.    The first  step  is to  place the bolus.
or mouthful,  upon  the  back part of the  tongue,  when  by

 Of what great use are the Kidneys? 310.  Describe tho process of Mastication. 01
what use is the Saliva? How much is secreted every day ? What increases its amount?
311. Describe the process of swallowing. 
AND  PHYSIOLOGY.              173
the muscles  of the tongue  and fauces it is forced into the
Pharynx.  As soon as it  fairly enters  this passage, the mus-
cles  by an  involuntary movement  seize it, and  force it rap-
idly  past the opening into  the  lungs,  and  at  the  same
moment  the  epiglottis  is forced  down upon  the larynx, to
prevent its entrance into the trachea.   This  part of the pro-
cess is involuntary, from the necessity of keeping the passage
to the  lungs  open  as  much  as possible, in order to admit aii;
and also from the great danger of introducing any other sub-
stance.  And so perfectly carried on is this function that it is
seldom—compared with the frequency of  deglutition—that
even  a fluid escapes the vigilance of this sentinel.
   312. Passage of the Food  through  the Esophagus.—The
food passes slowly through the Esophagus into  the stomach,
it being  forced along  by  the contraction  of the  muscular
fibers,  aided by the oily secretion of the Esophageal glands.
   313. Gastric Digestion.—As soon as the food reaches the
stomach, the most important part  of the  process of digestion
commences, all the previous steps being preliminary.  When-
ever any solid substance  comes in contact with  the inner or
mucous membrane of  the stomach, it excites  the gastric glands
to pour out in abundant quantity the Gastric fluid.
   314. Gastric Fluid—its Amount—Pepsin.—This fluid is
a transparent liquid of a little greater consistency than water,
and of a perceptibly acid  taste.  It possesses the property of
coagulating albumen, and of separating the whey or serum
from the milk in a very short time, and is secreted at the rate
of seventy ounces per day.  This property, however, is owing
to a peculiar organic compound called Pepsin, which acts after
the manner of a  ferment at  the  normal  temperature of the
human body.   The  Gastric  fluid also possesses antiseptic

  What part of the process is under, and what part is not under the control of the will?
812 Howls the food carried  through  the Esophagus? 313.  Where does the most im-
portant part of digestion take  place? What effect has any solid substance upon the Gas-
tric Glands of the Stomach ?  814. What are the properties of the Gastric Fluid ? How
much is secreted daily ?  What effect has it on the decay of substances ? 
 174           HITCHCOCK'S  ANATOMY

 properties, or  the power of preventing decay or putrefaction
 for a long time.   These  three properties, the acid,  fermenta-
 tive,  and antiseptic, are of  service in the following manner.
 The acid assists in the  solution of the different materials in
 the stomach.  The Pepsin,  which constitutes two  thirds of
 the solid materials of the gastric  juice, does its office by es-
 tablishing the lactic  fermentation, such as  is seen in  the
 cianges through which milk passes in  hot weather.   The
 antiseptic properties are  important  in order to prevent  putre-
 faction, which would  be so liable to be set up among organic
 substances in such a condition, and at such an elevated tem-
 perature as the stomach usually possesses.

   315. Digestion  partly dependent on  Chemical Action___
 Thus we see that this part of digestion is mainly a chemical
 affair, although  not entirely  so: since  by experiments care-
 fully conducted in a vial outside of the body, maintaining the
 same temperature and all the essential conditions of digestion,
 the process  goes on very  slowly and quite  imperfectly.   It
 was found, however, that a piece of meat  did digest  in a vial
 in nine hours and  a  half, while that in  the stomach  under
 precisely similar circumstances, was digested in one hour and
 a half.

   316. Digestion partly a vital Process.—Consequently  to
 say exactly what stomach digestion is, must at present be im-
 possible.  We can only say that  it is a chemico-vital process,
 essentially a chemical  action depending upon vital power.

   317. Movements of the  Stomach in  Digestion.-In order
 to bring the food in contact with the largest amount of Gastric
<Fluid, the stomach, by an  instinctive  movement, carries its
 contents over  the  greater curve  in it,  from the right  to  the
 left, and returns it in  a reverse direction, occupying  about

  What constituent is it that is primarily essential in this process?  815. How much of
 the process thus far described is mainly a chemical one ?  What experiment proves it ?
 816. What definition can be given of Digestion ? 317. What instinctive movements doei
 the stomach seem to possess? 
4
AND  PHYSIOLOGY.
175
three minutes for each revolution.   And in order that all  of
it  may be  permeated  by this fluid, contractions  frequently
take place in the muscular coat of the stomach, resembling a
churning process.
   318.  Intestinal  Digestion,  Chyme.—The process  thu.
far is Gastric  Digestion, or that which takes place in th^
stomach, and the object accomplished  seems to be  the  con*
version of the  nitrogenous constituents of the food into albu-
minose called histogenetic digestion, or the preparation of the
food to be made into the tissues of the body.   But  when  all
the food  is thoroughly dissolved, or made into a liquid condi-
tion called  Chyme,  the  Pyloric orifice is opened, and the food
passes into  the Duodenum.  When it arrives here—and never
sooner, in a healthy state—the secretions of  the  Liver,  Pan-
creas, and mucus of the Intestine mix with it, performing the
second or Intestinal digestion, which is called calorifacient or
heat  making, since it prepares the food which supports the heat
of the body.   The process,  however, is somewhat obscure,  al-
though it is certain that food is not perfectly fitted for absorp-
tion until it has well completed this process.
   319. Use of  the Pancreatic Fluid.—The Pancreatic Fluid
secreted at  the  rate of from  five  to seven ounces  per day,  re-
sembles quite closely the Saliva,  converting starch into sugar,
and aiding  in the absorption cf  fatty matters, by forming an
emulsion, which, however, is much more readily formed  by
the presence of bile.
   320.   Action  of the Bile,  an  Antacid  and  Excre-
tory Agent.—The  Bile, thrown out at  the rate  of fifty-four
ounces a day, seems from its  large  quantity  to  be of no
little  importance.  And  since the  juices of the stomach  are
mostly acid in their character,  it seems desirable that  there
should be some counteracting agent, which is furnished in  the
 318. What is the principal thing accomplished by stomach digestion?  What is food
called after it has passed through this process?  Describe Intestinal digestion and its
use.  319. What amount of Pancreatic fluid U secreted daily ? What is its principal use ?
320. How much Bile is secreted daily ? 
176
HITCHCOCK'S  ANATOMY
 highly alkaline  character of the biliary secretion.  Another
 use of the  bile is to remove certain materials from the blood
 (the carbonaceous), by allowing them to pass off with the
 waste portions of the food, the liver thus performing the office
 of an excretory organ.  The liver also seems to  possess the
 power of forming sugar and even fat, when it is not contained
 in the food, thus seeming  to act the part of an equilibrator in
 the process  of blood  making.   And since all  the blood re-
 turning  from  the small  intestines  passes through the liver
 before going to the heart,  without doubt an important change
 is accomplished in it by the liver, although the  change i3 as
 yet by no means fully understood.
   321. Purposes for wi.ich Food is  required.    Two kinds
 of Materials  in  the Food,  azotised and  non-azotised.
 Azotised Constituents.   Albumen, Fibrine,  Casein, Gela-
 tin.—In  the animal body  we find that food is required for at
 least three purposes :  First, to build up the organism  at  the
 outset, or, in other words, to secure its  first growth.  Second,
 to maintain the  organism at  its  normal standard after its
 growth is complete, or to  furnish material  to supply the waste
 which  is perpetually  going  on  while  life lasts.   Third, to
 maintain  the proper temperature  of the system.  Hence there
 must be  at least two kinds of material contained in the food:
 one that will sustain and  promote the growth of  the tissues
 called  histogenetic,  and another that will keep up  the heat of
 th j body  to a proper standard, called calorifacient.   The first
 of these requisites is found in food containing Nitrogen, called
 azotised, and the other in that with no  Nitrogen, called non-
 azotised.  Of the azotised food the most important constituents
 are Albumen, Fibrine, Casein, and Gelatin. Albumen is fami-,
 liarly known as the transparent portion of an egg  before it is
 cooked, or the white of the egg after a cooking process.  It ex-
 ists also in the blood, muscles, and bones of all animals,  and is

  How is its alkaline character serviceable ?  What other processes does it accomplish ?
321. What three purposes is food required for ?  Hence what two kinds of food must be
brought into the system ? Give examples of azotised food. 
                  AND  PHYSIOLOGY.              177

 coagulated  or made hard  and white  by heat or mixture with
 Nitric Acid.   In some parts of vegetables also, especially in
 the seeds and  fruit, is found  a substance which,  from its re-
 semblance to animal  albumen, is called vegetable albumen.
 Fibrine exists in  the  blood  and muscles of animals, forming
 the coagulum or clot  of blood, and the proper muscular sub-
 stance.   There is also a corresponding substance in plants
 known as vegetable Fibrine.   Casein closely resembles Albu«
 men in its  constitution, but  differs in  many of its  physical
 properties.  For while Albumen is coagulated by heat,  Casein
 is only coagulated by lactic and acetic acids.  Casein is best
 seen in cheese.   These three substances  are the essential ele-
 ments of  nutrition in  mamimK and though every other prin-
 ciple may be supplied  in the food, yet  the body is insufficiently
 nourished  without Albumen and  Fibrine.   Gelatin,  which
 exists  abundantly in  the  cartilage  of  animals,  is another
 azotised principle of  food.   This, however, of itself can not
 support  life,  although it  can be  changed  into albumen,  or
 some of  its compounds by the action of  the  fluids of the
 stomach.
   322.   Non-azotised Constituents.— Of the  non-azotised
 constituents  of food,  the  Saccharine and Farinaceous and
 Oily, are the principal ones, although there are many others
 of less importance.   Of the former, the principal element  is
 starch, while the sugar is  secondary or subsidiary to it, and
 in the latter we find an abundance  of a  Hydro-Carbon, or a
 compound of Hydrogen, Carbon, and Oxygen,  and  all are
 essential elements in combustion.

   323.  is an exclusively Animal  or Vegetable  Diet the
 best  adapted  to  Man?  Testimony of  Experience.   Ex-
 perience  of Dr. Kane.—The question then  which naturally
 suggests itself here is, Avhether man is adapted to live ex-

  What effect has heat and Nitric Acid upon Albumen ? Where is Fibrine found ? How
does Casein differ from Albumen?  Will Gelatin (or Jelly) of itself support life? 822.
 What are examples of non-azotised kinds of food?  323. Is man made to live on an ex-
clusively vegetable or animal diet ? 
178
HITCHCOCK'S   ANATOMY
clusively upon vegetable or animal  diet.  An  answer cornea
to us from both experience and chemistry.   For while on  the
one hand hundreds of examples are  adduced, as showing that
some men have lived to a green old  age in solid  health, who
have  entirely refrained from  animal  diet, and many others
who  probably  would  have shortened  their  lives a  score  of
years by the use of animal food, have prolonged it by adopt
Jhg a vegetable regimen, an equal  number of cases can  be
mentioned to show that a mixed diet has promoted equally
long and healthy lives.  The geographical distribution of man,
as well as the manner of life, also furnishes valuable evidence
in this case.  Travelers who have visited the polar regions, and
pre-eminently Dr. Kane, give us undoubted  testimony of the
necessity  of  eating meat and animal fat to keep the body in
health: since the low temperature not only requires a greater
amount of combustive material, but this  greater energy  of
respiration produces a  more rapid waste of all  the tissues of
the body, requiring a more abundant  supply of azotised and
non-azotised material to supply the deficiency.  And on the
other hand  experience shows that in tropical climates stimu-
lating food and  drink should be  avoided,  because the high
temperature  of the atmosphere depresses vital energy, and
consequently less material for  supporting animal  heat is  re-
quired  with a  corresponding  decrease in the  waste of  the
body.
   324.  Example of the  Esquimaux.—As examples of these
principles one traveler among the Esquimaux relates that these
people relish very heartily tallow candles as a dessert for din-
ner.   Another states that he  has seen  the Greenlanders eat
from  twenty to thirty pounds of blubber, or whale-fat, at one
meal.   This, however, was a sufficiency of food to  them  for
two or three days.

 Give  the testimony of experience.  Give the argument derived from difference in
climate. What kind of food is necessary to support  life in polar, and what in tropical
countries ? 324. State luxurious articles of diet among Esquimaux and Greenlanders.
How much will a Greenlander sometimes eat ? 
AND  PHYSIOLOGY.
179
   325.  Voice of  Chemistry —Chemistry,  however,  teaches
us that we can  find  in  the  vegetable world all the principles
necessary to  support the body without  using animal  food.
And although the vegetable kingdom contains those  elements
which will  support  life in many instances,  yet  we know,
as a  general ride, that we find man in  the highest degree
of bodily  and  mental  vigor,  only  when  he  makes  use of
 i mixed diet.  And  we also find that all  animals which are
the most active  in their  habits,  and rapid in their motions, are
feeders upon animal  flesh.   There is also a race of half civil-
ized  savages, the Guanchos, who spend the greater part of
their lives  in the saddle  and  constantly in a state  of great
activity, who live almost exclusively upon animal diet, and
yet are unequaled in their powers of physical endurance, and
live lives fully  equal to the average  in duration.
   326.  Argument from the Teeth.—The strongest  physio-
logical argument in favor  of  a mixed diet,  is found in the
conformation of the teeth and  alimentary canal of man.  In
those animals which live  exclusively upon animal  diet, the
 teeth are  sharp  and pointed,  with  a very short alimentary
 tube, since  the nutrient portion of the food is readily absorbed
 by the lacteals.   On the  other hand, the teeth of vegetable
 feeding animals are smoothed upon their upper surfaces, being
 adapted to  crush vegetable substances, and the alimentary
 tube very long, since the nutrient portion of vegetable food is
 not so  readily parted with.   Now in man  we find  neither of
 these apparatuses perfectly complete, but an  admixture of
 both.  Part of the  human teeth are of  the  carnivorous or
 flesh eating kind,  and another part of  the  herbivorous or
.vegetable  eating  kind  : but each of them so modified, that
 either  kind of food can be  readily  prepared for  digestion.
 The  alimentary canal too is intermediate  between that of the
 carnivorous and herbivorous type, being equally well adapted

  325  What does chemistry teach on this subject? How does great bodily activity
 affect the diet as illustrated by the Guanchos?  326. State the argument derived from
 the teeth.  What two kinds  of teeth are found in man ? 
180
HITCHCOCK'S  ANATOMY
to the digestion of animal or vegetable food, or an admixture
of both.
  327.  Conclusions.—The  kinl of food which is  the most
perfectly adapted  to the constitution of man, seems to be de-
termined by the following rules, based upon the temperature
of the climate,  the habits  or  employments  of life, and the
health of the individual.
  First.  The lower the temperature the greater the  amount
_f animal  heat necessary for the support  of life, which re-
quires the fattest portions of the meat.
  Second.   The more active the habits of the individual, and
the greater the amount of exposure in the open air, the greater
the demand for animal food.
  Third.  If the system  be suffering under inflammation of
any sort, or if there be any  tendency to inflammation, animal
food should  be used  very  sparingly, or  entirely  dispensed
with.
  Fourth.   That diet  seems to be the most perfectly adapted
to the human constitution in all climates  and seasons, which
is composed of animal  and vegetable food in the  proportion of
one to two, or one third  by weight of animal food to two
thirds of vegetable food.   This  proportion  is the basis  of the
diet scales 'of the United  States and British  Navies.
  328.  Use of the Lacteals.—The use  of the Lacteals is to
absorb the Chyle or nutrient material from the contents of the
intestines,  and .carry  it  into the  general circulation.   The
force by which this fluid is taken from the alimentary canal,
is by no means understood at present, unless it  be  capillary
ittraction.
  329.  The Chyle.—The  Chyle is  a white  liquid somewhat
(Viicker  than milk, and is  made up of a solution of albumen
containing minute  globules,  or cells, which  are mostly spher-

  8?7. What four conclusions are drawn from this whole subject of diet?  328. What is
thr function of the Lacteals?  What is  the force that circulates the Chyle?  329. De.
»cr>t>o the Chyle. 
AND  PHYSIOLOGY.
181
ical  and  about  3oiooth of an  inch thick, and  Chyle  Cor-
puscles, which are  simple cells  about eoVoth of an  inch in
diameter.
   330.  The  Place where the  Chyle  enters  the  Blood.—
Principle  of  Venturi.—As already mentioned the Chyle en-
ters the blood through the  left Subclavian vein  of the  neck.
It is not, however,  simply by the  opening  of one vessel into
another  that this is accomplished, but advantage is taken of
the  union of two currents,  so that by  their combined  force
the chyle is drawn  in towards the heart.   The mouth of the

                           Fig. 187.
    Position of the Thoracic Duct and the Veins of the Neck where it empties.
   S. V. Subclavian Vein.  J. Jugular Vein.  D. Thoracic Duct.

Thoracic  Duct, however, is provided with valves to  prevent
the blood from entering it, in case obstruction in the veins
should occur.   And " it is a physical fact that, when a small
tube is inserted perpendicularly into the lower side of a hori-
zontal conical  pipe, in which water  is  flowing from  the nar-

  Give the size  of the Chyle Corpuscles.  330. Give the description of the hydraulU
principle by which the chyle is drawn towards tho heart. 
182
HITCHCOCK'S  ANATOMY
                                rower to  the  wider  portion,
                                if the vertical tube be made
                                to dip into a vessel of Avater,
                                not only will the water of the
                                larger pipe  not descend  into
                                the  vessel,  but it  will draw
                                up  the  water  through  the
                                small tube so  as  to empty
                                the  vessel."   This is  called
                                 "the principle  of  Venturi,"
                                and is well illustrated by the
                                entrance of the Thoracic Duct
                                into  the Subclavian  vein, as
                                seen in  the cut No. 187.   A
                                diagram illustrating the same
                                principle is  seen in Fig. 188,
                                the  arrows  representing the
                                direction of the currents,  and
                                the   smaller,   perpendicular
                                tube illustrating the Thoracic
                                duct at its entrance  between
                                the veins of the neck.
   331.  The  Lymphatics.—The   Lymphatics  in  general
structure and  function resemble  the lacteals.    The  lacteals,
however, are designed exclusively for promoting the growth
of the body by adding nutrient materials, while  the  lympha-
tics give up to  the general  circulation  not only useful  pro-
ducts,  but all those which are absorbed.    Hence whatever  is
presented to the mouths of the lymphatics, is carried into the
general system, while injurious products are not usually taken
up by  the  lacteals.   (See also page 284.)
   332. The Action  effected by the  Lymphatics.—Since
the Lymphatics, as  already described, are found in  every

  Illustrate the principle of Venturi. 331. Give the general structure of the Lympha-
tics. State th« probable differences in function  between these and the Lacteals.
FiG. 188.
  Illustration of the Principle of Ven-
turi. When a current passes through a
large tube, if another smaller tube open
into its side, the current in this tube
will be drawn into the large tube, even
against the force of gravity. 
AND  PHYSIOLOGY.
183
part of the body in great numbers, and are almost constantly
at work in removing the  waste particles, it follows  that  in
process of time a large part, or even the whole of the body.
will be removed.   And it is  generally admitted that  the
whole  body is actually  renewed  every few  years, although
the precise number can not be  stated,  since so many  circum-
stances modify the change, such  as  exercise, the amount  of
food taken, and climate, as well as other  causes not so "easily
understood.   It  is,  however, quite probable that the period
of ten years is sufficient to complete the change in most in-
dividuals, and the number is stated by some as low as seven.


               HYGIENIC  INFERENCES.

   333.  1. From the structure and functions of the Digestive
Organs we can derive some hints as to  the manner  of pre-
venting acute and chronic diseases in them.
   334.  Danger of  Eating too much.—2.  We see that there
is a great danger of eating  too much.  Large quantities of
food distend the coats of the stomach, and give too much labor
for them to perform.  As a  natural consequence the gastric
glands are weakened from excessive action, and then  indiges-
tion or some other diseased action is sure to  follow.   And in
how much better health would multitudes in the higher classes
of society be  kept, if  some of  the numerous dishes  they use
were omitted!  And  in  this country  the  remark applies to
nearly all classes.
   335. We are  apt  to eat  too  many Kinds of Food.—3. We
also see that our meals are generally  made  up of too ma?iy
kinds of food.   In the  habits of the lower animals we dis-
cover a great simplicity of diet.  Even in those  whose  ana-
tomical structure closely resembles that of man, the appetites
  332. How great changes are effected in the body by the Lymphatics ?  In what length
oftimeisthebody probably entirely renewed?  334. What is  the injury from eating
too much ? 335. What is said about eating too many kinds of food ? 
184
HITCHCOCK'S  ANATOMY
are  easily satisfied by  the simplest food.   Nor does  man's
intellectual superiority demand  a greater variety in  diet, all
that is requisite being the materials necessary to support the
growth of the different tissues.
   335a.  4.  It is evident that condiments and spices should
be always used very sparingly,  and generally spices not at
all.   To be sure  nature seems to  indicate the want of  a mode'
rate supply of salt (perhaps  for the juices of the  stomach),
but  pepper,  mustard, and ketchup excite the  coats  of the
stomach  to an action that is unnatural.   And  it seems  to be
a  law of the  system that stimulants and  opiates,  if  used
regularly,  must  be constantly increased in  quantity, other-
wise they will  lose their effect, and disorder will follow.   In
fine, all experience seems to prove that the demands of nature
for food are very  simple and easily gratified;  but  the  appetite
may be so trained as  to loathe  every thing of a simple and
natural kind, and be satisfied only with the stimulating com-
pounds of modern cookery.   The law  of nature,  however,
cannot be reversed, that he who lives in the simplest  manner
lives the longest, and suffers the least from pain  or disease.
   336. We must not  eat too fast.—5.  Most  persons cat too
fast.  No time  is gained on the sum  total of life, by taking
any from that demanded  by nature  for eating and digesting
food.   A fortune or great  reputation, it is  true, may some-
times be  gained  a  little  quicker by  using  the  time which the
stomach  rightfully claims, yet the penalty for such robbery ia
a shorter life, or  a disease which makes life miserable.
   337. The  Time of Eating.—6. We see that  the time of
eating should not encroach upon the hours  devoted to sleepj
or those  of hard labor.   During sleep the brain needs quie£
but  if there  be  any function going on such  as that in th_
earlier stages of  digestion, the brain, as a matter of necessity,

 Does intellectual superiority require so great a variety as is often introduced?  385.
Why are condiments and spices to be used very sparingly?  What are the demands ot
nature upon the appetite? IIow much may the appetite be perverted?  836. What
danger in eating too fast?  337.  What time during the day should we eat? 
AND  PHYSIOLOGY.              185
must labor till  the process is  accomplished, and as a result,
dreams or  imperfect trains of thought will produce  that kind
of sleep  which cannot refresh  the  body.  If again  the time
for meals precede  or  folloAV  very closely upon  hard  labor, a
law  of nature is broken, and  the  penalty is sure  to follow.
The  nervous  energy  cannot be  immediately called off from
the part  to which it has for some time been directed (whether
to the brain  or  the muscles), and  consequently the stomach
for a while must lie nearly inactive.   Hence a short season
of relaxation from all active  exercise,  whether mental or
physical, just before  and  after  meals, is very  conducive to
health, since in the former case the circulation  is equalized,
and  the brain can prepare its energies to expend them on the
stomach, while after meals  the  whole force of the nervous in-
fluence is needed for a time by  the  digestive function before it
can  be directed  to the muscles  for exercise.   Even a short
time after  dinner devoted  to a nap promotes digestion  quite
rapidly,  although  the habit often  is  an  inconvenient one, to
say  the least, since if by unavoidable circumstances it is omit-
ted  for once, the person feels  uncomfortable the rest of the
day.

   338. Danger of employing Stimulants  for weak Stom-
achs .—7.  We see  the error and  danger of a  very common
practice: that when the digestive  organs become weak, and
the  aj.petite is poor, stimulants are employed  to waken the
stomach to crave more food than it can digest.   This  only
aggravates the difficulty and  makes  a demand for stronger
stimulants, and thus  often is  the  system prematurely  worn
out.    Whereas, would men follow  nature and when a dimin-
ished appetite teaches them to eat less and give the  organs an
opportunity to rest, they would ere long rally  and  digest all
that is necessary to give tone and energy to  the system.   To

  Why should  not hard labor and a full meal come closely together? How does a short
nap after dinner affect digestion ? What is a serious objection to the habit?  338. What
danger results  from using stimulants to help weak stomachs ? Should we  eat more than
the natural appetite craves ? 
186           HITCHCOCK'S  ANATOMY
eat more  than the stomach craves,  is not  the way  Lt gain
strength, but to increase weakness and shorten life.
        COMPARATIVE SPLANCHNOLOGY.

  339.  Digestive  Organs of  Mammals.—In many  mam
mals the digestive  organs in  their general  arrangemvnt and
construction resemble those of man.
Fig. 189.
Parotid Gland.
Maxillary Gland.
     Trachea.
      Colon.
     Caecum.
Small Intestine.
                   Digestive Apparatus of an Ape.

  340.  Esophagus  of  the  Horse,—In  the  Horse, however,
at the lower end  of the  Esophagus, there is a sickle-shaped
340. How does the Esophagus of the Horse differ from that of a man ? 
A N D  PHYSIO L O G Y
187
fold of lining membrane, which makes  it  impossible for this
animal to vomit.
   341.  Stomach  of  Ruminants.—Mammals,  as  a general
rule,  have  very  simple  stomachs,  and  particularly   those
which live  upon  animal  food,    But  in those  herbivorous
ones which chew the cud, this organ consists of four cavities,

                            Fig. 190.
          Gullet.


Esophagean Groove.

       Maniplies.



       Duodenum.
Pylorus. The Rennet. 2d Stomach. Paunch.
     Stomach of the Sheep.
the  Ingluvies  or   "Paunch,"  the  Reticulum  or  "Honey
Comb,"  the Omasum or "Many Plies," and the Abomasum
Fig. 191.
         Gullet.

Esophageal Groove.

Maniplies, or Third
    Stomach.
Eennet, cr Fourth
   Stomach.
Pylorus.         Second Stomach.
     Interior of Stomach of the Sheep.
Paunch.
 S4„ What is the number of stomachs in herbivorous animals ? Give the names o
»_ah. 
188
HITCHCOCK'S  ANATOMY
    ticulum.  C. Omasum.   _>.  Abomasum.    .      .     *?
    E. Pylorus.  F. Duodenum.  G. Esopha-    mg  With   the   Saliva.
                                      After  this  process  is
completed,  they  are  sent  into  the Omasum,  which  cavity
seems designed  to prepare the food  to enter the fourth stom-
ach  where  the  true process of  digestion takes place.  And
it is from this fourth stomach  or  Abomasum,  that  the  Rennet
is taken from young calves, and used by cheesemakers for  the
purpose of  coagulating the milk.

  342.  Reason   of this  Complex  Stomach.—The probable
reason of such a complicated stomach  in these animals is that
since they have such poor means of self-defense, they  need to
crop their food  as quickly  as  possible,  and then  retire to a
safe place to masticate it.   And  it is also partly owing to  the
fact  that vegetable substances require  a  longer  process for  di-
gestion than does animal food.

  343. Length  of Intestine.—The length  of  the  Intestine
depends as a general rule upon the food used  by  the  animal,

 Give the process of chewing the cud in these animals.  342. What is one  important
reason for this complicated arrangement?  343. Upon what does the length of Intestia*
depend? 
AND  PHYSIOLOGY.               189
the vegetable feeders having a long tube, and the flesh feeders
a short one,  since animal food is so easy of stomach digestion,
and the nutrient  portion  of it so  readily taken  up by the
lacteals.  Thus  the ox has  an  alimentary  tube  fifteen or
twenty times  the  length  of the body,  amounting in a full
grown animal to 150 feet, the sheep one twenty-eight times its
length, while  many of the carnivora exhibit  one  only  about
iLree times the length of the body. The true Cetacea or Whale
tribe are the only  ones which do  not  have a  marked distinc-
tion between the large and small  intestine.
   344.  The Liver.—The   Liver as  in  man is one of the
largest organs  in  the body, and is much more divided into
lobes in carnivorous than herbivorous animals.   It is smallest
and least  divided  in those animals with compound  or  rumi-
nating stomachs.
   345.  Rill of Birds.—Birds  are  destitute  of teeth,   since
the process  of mastication is carried on in  a certain portion
 Df the alimentary canal.   But the horny investment of the
 jaws known as the bill, is harder in birds of prey, and  those

                            Fig. 193.
Tonga*.
Os Hyoides.
                     Head of the Woodpecker.

that feed on fruit and nuts, as Parrots, and in Woodpeckers.
The bill, or rather mouth, of Ducks  and  Geese is lined by
a tender  membrane,  in order  that they  may  be partially
 What is the length of the Intestine  of the Ox?  Of the Sheep?  Give the propor-
tional length of Intestine in Carnivorous Animals.  344. What difference in the Liver
between flesh  and herbivorous animals?  345.  Why are Birds destitute of teeth?
What Birds have tho hardest bills?  What peculiarity in the lining membrane of the
mouth of Ducks, eto. ? 
.80
hitchcock's   an a to m y

              Fig. 194.
   Digestive Apparatus of Fowl.  a. Esophagus,  b. Crop or  Ingluvies.  c. Pro-
  ventriculus.  d. Gizzard,  e. Liver.  /. Gall-Bladder.  g. Pancreas,  h. Duodenum.
  i.  Small Intestine.   „.  Cieea.  I.  Large Intestine,  m. Ureter,  n.  Oviduct.
  o.  Cloaca.


guided in the selection of their food from the soft mud by the

sense of touch.


   346.   Stomach   of  Birds. —The  Gizzard. —The   true

stomach of birds  consists of two divisions.   There are, how-
346. State the usual number of stomachs in Birds. 
AND PHYSIOLOGY.               191
ever, three enlargements of the alimentary canal, all of which
prepare  the food for assimilation.   The first of these is the
'•Ingluvies'' or  "Crop," where the food  is softened by the
mucous secretion of the lining membrane.  Then  as it passes
along into the " Proventriculus," it receives the gastric juice
from the  gastric glands which  line it.   The second stomach,
the  "Gizzard,"  is  round  and  flat and made up of powerful
muscular fibres,  except in birds of prey, where it is  thinner
in texture.  In  gallinaceous  birds its lining membrane is of
a horny consistency, which, with the powerful muscular fibres,
render it an organ of mastication to  granivorous birds.  Gravel
and angular stones are purposely swallowed by these birds
to aid in the digestive or grinding process.

   347.  Teeth  and  Jaws of  Reptiles.—Reptiles need teeth
only to  seize and  retain their prey, since whatever food is
taken by them,  is swallowed without  mastication, which is
one reason why  the jaws and
              J     J                     Fig. 195.
throats  of  serpents  are so
very capacious.   A  peculi-
arity in their bony construc-
tion renders   this  possible,
for  the   jaw is  not  made
up  of  one or  at  most  two
pieces as in mammals, but of
several  segments,  which rea-
dily move one upon another,
as if with different articula-
tions.
   348.  The Tongue.—The Tongue is used as an instrument
for  the capture  of prey by many  reptiles.   Frogs  and Sala-
 manders  are able  to  thrust it out with  great rapidity and
 Head of the Rattlesnake,  mi. Lower
Jaw.  t. Tympanic Bone.  ma. Mastoid
Bone. m. Upper Jaw.
 Give the names of each. Describe the Gizzard  Why are gravel and stones swallowed
by granivorous birds ?  Which is the true stomach ? 347. What is the only use of teeth
in reptiles?  State the reason why the jaws are so capacious.  Of how many bones ar«
they frequently made up ? 318. Of what use is the tongue to some reptiles? 
L92
HITCHCOCK'S   ANATOMY
 coil it upon insects  or  any other object.  This property, to-
 gether with the adhesive mucus found  upon it, makes it for
 these  animals  a  very  serviceable  apparatus  in  obtaining
 food.

   349.  Esophageal  Teeth.—In  many  animals  of  this de-
 scription the Esophagus  is lined with  bony processes pointing
 downwards,  called Esophageal teeth, which greatly aid in
 swallowing the large masses which they are  accustomed to
 force into their stomachs.

   350.   Stomach. —Length  of  Intestine.—The  Stomach
 seems to be only a  dilatation of  the  Intestine.   In many
 species it is divided  into two cavities resembling  those of a
 bird, (Fig. 196) :  the first a Gizzard, or an organ  made up
 of stout  muscular fibers, and  the second a  thin walled  and
 secreting cavity.   In  Crocodiles it is round, and the muscular
 coat is very thick, in order to  reduce to  a digestible  size
 the  coarse  food which it  so  greedily devours.   The length
 of the intestine in most reptiles is about twice  the length
 of the body ;   in  Lizards, however, it  is  only  about  the
 same length as the  body.   A cloaca or additional rectum
 is sometimes found in these animals, as is  the case among
 birds.

  351. Stomach and  Intestine of  Fishes—In many Fishes
the intestinal tube  extends  from  the mouth  directly through
the animal without any enlargement for  the stomach,  or any
convolutions, as is  the case with all the animals thus far con^
sidered on this subject, and with which no organ of secretion
is connected, except the liver.   The intestinal canal, however,
is generally more or less convoluted,  and  ordinarily it is short!
In the Shark the stomach is parceled out by constrictions and

__T w, ^^ ,S-, T. red',that rendCrS " m°re service^le as an instrument of capture ?
M What is said of Esophageal teeth? 350. Is the stomach a simple or complex cav
S f  w * th° 8Verage !Cngth ofint68ti"e am°n« ™Ptiles ? What is said of a cloaca?
withlith ShC°k?    'S the8t°mach found in m»st fishes? What peculiarity is met 
AND   PHYSIOLOGY.
193
Fig. 196.
  Anatomy of the Common Snake.  I. Tongue,  m. Esophagus, i. Stomach.  V. Sm_V
Intestine,  cl. Cloaca. /. Liver,  o.  Ovary,  o'. Eggs.  t. Trachea,  p. p'. Lungs,  vi
Ventricle,  e. e'. Auricles, a. ad. a'. Aorta,  ac. Carotid Arteries,  v. vc. Vena; Ca>«
r . Pulmonary Vein.
inversions into  several  divisions  with valve-like  appendages
between them.
   352.  Liver. —Fishes  have usually a large soft  Liver com-
pletely  saturated  with  an oil.   Its  form is various,  but  is
352. Speak of the Liver of fishes. 
I 94           HITCHCOCK'S  A X A T O M Y
often imperfectly divided into  ti
pressed from the liver  of the
great efficacy in the  early stages
            Fig. 197.
 Digestive Apparatus of a Beetle,  a.
Head. b. Crop and Gizzard,  c. Biliary
Vessels, d. Intestine,  e. Secreting Or-
gans.
and to disgorge the refuse, as is
Polyps, however, have two open
as shown in Fig. 198, B.
vo lobes.  The oil that is ex-
Cod  Fish,  is  often  used  with
or symptoms  of consumption.
   353. Pyloric  Appendages,
 —In many fishes  with bony
 skeletons there is found a cu-
 rious set of gland-like organ i
 called  Pyloric  appendages,
 They  vary in number from
 two  in the  Plaice,  to   two
 hundred in the Mackerel, and
 always  either  encircle  the
 pylorus,  or  are found  near
 the upper end of the intestine.
 These  appendages  are  inva-
 riably  absent in those fishes
 which  have  an  impeifectly
 formed stomach, and by some
 are  considered as  analogous
 to a Pancreas in function.
    354.  Salivary Glands.—
 Salivary Glands are wanting
 in fishes, but their place is
 supplied  by an increased de-
 velopment  of  the  mucous
 glands of the mouth.
   355. Digestive  Organs in
 the  Invertebrates.—In  the
 Polyps of  the Radiate  ani-
mals, we  have the  simplest
 form of digestive  apparatus,
 viz., a simple sack, with a
 mouth  to  receive  the  food
seen  in Fig. 198, A.   Other
Dgs in their stomach or sack, 
and  physiology
       Fig.  198.
195
               Digestive Apparatus of Unicellular Animals.
  356. The  Hydra.—Fig. 199, an  unicellular animal, is an
example where the simplest sort of digestive  organs  is ex-
hibited.   The animal is little
else  lhan  a  gelatinous  sac,
and if it be turned inside out
digestion will  still  go  on.
Thus,  "notwithstanding  the
simplicity  of its structure,
this creature feeds not merely
upon algae, but upon young
active  animalcules, the young of
crustaceans,  etc. ; any one of
these,  when  they happen to
came in contact with one of
the tentacular filaments, be-
ino-  usually  retained   by
adhesion to  it.    As   this
filament  shortens  itself, all
the  surviving filaments  ap-
ply themselves to this captive
Fig. 199.
 Hydra or Fresh Water Polyp.
trance and Exit to Stomach.
a. E_
particle, so  that  it  becomes gradually inclosed,  and grad'
356. What is the process of digestion in the hydra ? 
1&6
HITCHCOCK'S  ANATOMY
ually shortening, so as at last to bring the prey close to the
surface of the body.   The spot with which  it is brought in
contact, then slowly retracts, and forms at first a shallow de-
pression, gradually becoming deeper and  deeper,  into which
the prey sinks little by little,  for some time, however,  con-
tinuing to project from  the surface.   The depression at last
assumes a flask-like form, by the drawing in of its margin,
and finally its edges close together,  and its  prey is entirely
shut  in.  This  gradually passes to  the center of the body,
where its soluble parts are dissolved, whilst in the mean time
its external portion recovers its pristine condition."
   357. Other Radiates have an  alimentary canal more  com-
plicated, having a stomach and csecal appendages that appear
to perform the office of a liver.   Some of  the  Echinoderms
have  teeth; in  the Echinidse  is a curious apparatus in  the
mouth called Aristotle's lantern.
   358. Another f o r m of the digestive  apparatus consists of a
central cavity, with  branches  extending through  every  part
of the body.  Fig. 200 shows this in one of the Articulated
animals, an Arachnoid Crustacean,  the Ammothea pycnog-
onoides.  This arrangement is  found  in several  other classes
of the Invertebrates.
   359. The Crustaceans are generally furnished with two
upper jaws, called Mandibles, which  move laterally; and be-
hind  these,  two  pairs  of weaker and  softer lower jaws, which
are sometimes changed into suckers and  legs.  The higher
branches are always provided with prehensile organs for seiz-
ing the food, which are arranged  in pairs.
   360.  These are  best  seen in the Lobster, where they are
enormously developed,  projecting in  front of the eyes a dis-
tance nearly equal to that of the length of the whole body,
and each extremity is furnished  with a powerful pair of pincers.
Some of the higher Crustaceans have  a sort of horny teeth
implanted in the coats of the  stomach which are worked by a
359. What are the jaws of crustaceans? 
AND  PHYSIOLOGY.               197


         Fig. 200.
  Digestive Organs of Ammothea pycnogonoides (Crustacean), a. Esophagur  b. Stom-
ich. c. Intestine.  _. Digestive Cavity of the Jaws.  e. Digestive Cavity of the Legs.

powerful  set of muscles, which help in the reduction of the
food.   These  teeth are found in the Lobster's stomach.   The
stomach of the Leech is very capacious, being nearly the size
of the whole body.  The same is essentially true of the com-
mon Earthworm, which is an  Annelid.   In  many insects
salivary glands are present, and in  such cases they are placed
at the commencement of the alimentary canal.  The different
parts  of the alimentary canal  in insects " may be properly
distinguished  in  the  following manner.   The first portion is
the Esophagus, muscular, occupying  the three thoracic  seg-
ments  and  often dilated at its posterior  part into  a  crop
(Ingluvies) and muscular gizzard  (Proventriculus).  Some-
times there is appended to  the  Esophagus a sucking stomach, 
7 98              HITCHCOCK'S   ANATOMY
Fig. 201.
  Aplysia (Mollusc) laid open  to show the viscera,  a. Esophagus,  c. Salivary  Glands.
d. Cephalic Ganglion,  e. Esophageal Ganglion. /, g. First Stomach or Crop. h. Third
or True Stomach, i. Gizzard,  k.  Intestine.  I. Liver,  m. Posterior Ganglion, n. Aorta.
o.  Hepatic Artery,  p. Ventricle  of  Heart,  q. Auricle,  r.  s. Branchiae or Gills.  *
Lower Intestines,   v. Ovary. 
AND  PHYSIOLOGY.
199
consisting of a more or less pedunculated thin walled vesicle,
which  is multiplicated on  itself when empty.   The  second
portion consists of a stomach (ventriculus) in which the chyle
is formed, and  which  is continuous at the point of insertion
of the malpighian  vessels with the third portion of the digest-
ive canal.  This third portion commences by a small and usu-
ally short ileum, which  is  followed by a  colon  larger and of
variable length.   This last  often has a caecum at its anterior
extremity,  and  terminates  posteriorly in a short,  muscular
Rectum."
   " A considerable  number of insects take no food  during
their perfect state, the object of their existence  being  only to
accomplish  the  act  of reproduction.  Their jaws  are often
very rudimentary, and are fit neither  for sucking nor for
masticating."
   361. The  Annelida have  sometimes  quite complicated
jaws, even as many  as eight or nine, moving laterally.  They
have also salivary and hepatic  glands, as  have many other
invertebrates.  These are  shown on Fig. 197, which repre-
sents the whole alimentary  canal of an insect.

   362. The Cephalopod Molluscs have  a mouth, two horny
 jaws moving vertically in the pharynx,  a tongue, an  oeso-
phagus, a stomach, a pylorus, and  an  intestinal canal.
   363. In the Cephalophora the jaws move laterally for the
most part.   In the whole  class we find a biliary  apparatus
and generally salivary glands.   Fig. 201 shows the digestive
organs of a Gasteropod, the Aplysia.  Nearly all the Ceph-
alophora have  a  longer or shorter  fleshy mass attached to
the base of the pharynx that is comparable to a tongue.  It
has a longitudinal grove in it, and is sometimes included in a
sheath.  It is always covered with horny denticulated plates
and spines, which are very delicate,  and  arranged in quite
elegant longitudinal and transverse rows.   The points of these
spines turn backward, which aids greatly in swallowing. 
200           HITCHCOCK'S  ANATOMY

  364.  In some families of the Entozoa—the  Cystici, the
Cestoclesand Acanthocephali—there is no mouth nor proper
intestinal  canal, but there are vessels  for  the circulation of
nourishment  which is  received directly through the sides of
the body,  on  the principle of endosmosis. 
CHAPTER   FOURTH.
THE CIRCULATING SYSTEM.—ANGIOLOGY, OR HISTORY OF
          THE  ORGANS OF BLOOD CIRCULATION.
DEFINITIONS   AND   DESCRIPTIONS.
   365.  The  Circulatory   Or?
this system  are  the  Heart,
Arteries,  Veins,  and  Capil-
laries, and are mainly  tubes
of  various  diameters   and a
hollow organ, with the double
office of receiving and  propel-
ling the blood.
   366.   The   Heart. —The
Heart, or  central  engine  of
circulation*,  is located in  the
thorax or chest, resting  by its
lower  surface  on   the  dia-
phragm, and somewhat to the
left of the middle line of the
body.    It is of a conical form,
made of animal muscular fiber,
the fibers crossing themselves
in  at  least three  directions;
and it is a singular  fact that
ans.—The  organs  composing
             Fig. 202.
                B.1H  _'o
 An Anterior view of the Heart in a Ver-
tical Position, with its Vessels injected. 1,
Eight Auricle.  2, Left Auricle.  3, Eight
Ventricle.  4, Left Ventricle. 5, Descend-
ing Vena Cava.  6, Aorta.  7, Left Pulmo-
nary Artery.  8, The Arteria innominata.
9, Left Primitive Carotid.  10, Left Sub-
Clavian Artery.  11,  Anterior Cardiac Ves-
sels in the Vertical Fissure.  12, Posterior
Vessels from the Transverse Fissure. 13,
Main  Trunk of the Pulmonary Artery.
 365. What are the organs used for the circulation of the _lood ?  366. Give the location
of the Heart. 
202
HITCHCOCK'S   ANATOMY
                                 many of the fibers of the heart
                                 anastomose, or join with each
                                 other in  many  places, as is
                                 seen in  Fig.  203.   The heart
                                 is  a double  organ,  one  side
                                 being called  the arterial and
                                 the  other  the venous, or left
                                 and right hearts,  since the for-
                                 mer receives and propels the
                                 pure  or arterial blood, while
Anastomosing Fibers of the Human Heart.   the  latter circulates  VenOUS
blood.   Again,  each of the two sides  or hearts are divided
into an auricle and a ventricle.   Each of these  four cavities
will ordinarily contain about  three  fluid  ounces, making the
whole heart to contain nearly a pint.
   367.  The Auricles  and  Ventricles.-The   Auricles are
the uppermost cavities of the heart, and  are somewhat smaller
                            Fig. 204.
                       vj  ac  t  ac  vj
Bight Lung
Left Lung.
                        od    vc vd a     vg
  Lungs, Heart, and Principal Vessels in Man.  od, Eight Auricle, vd, Eight Ventricle.
vg, Left Ventricle,  a, Aorta,  ac, Carotid Arteries,  vc, Vena Cava, t. Trachea,  vj,
J<igular Veins.
  What are its shape, size, and four cavities called?  What is the capacity of an adult
fceart ? 
AND   PHYSIOLOGY.
203
than the  Ventricles, or lower ones.   The  auricles also have
the thinnest walls, and are  capable of considerable  dilatation,
since by  a  sudden effort of the body the blood is liable to be
sent in great quantities to  the heart, and  the veins would be
in danger of rupture were there no elasticity in the receptacle.
The thickened walls of the  ventricles give increased power of

                             Fig. 205.
            Vena Cava Sup. Art. Pulm. Aorta. Art. Pulm.

                        \    \     1     /
                                /^yisHK  -^.......... Pulmonary Veins.
     Pulmonary Veins-  -   "*=  '^*' ■'"  -*■
        Eight Auricle. - ..... SPffH [^UmWmll..........."  Left Auricle.
       Tricuspid Valve. -         && «^         '  Mitral Valve.
    Vena Cava Inferior.
Eight Ventricle.  '"
Left Ventricle.
                        Septum. Aorta.
                 Theoretical Section of the Heart in Man.
contraction.  This is needed because the ventricles drive the
blood from the heart, and the auricles receive  it on its return.
The right  ventricle, however,  propels the  blood only to the
lungs, while the left ventricle sends it to all parts of the body
except the  lungs.   The  left  auricle receives only the blood
from the lungs, while the right auricle receives it from all the
other parts of the body.

   368.  Valves  of the Ileart.—Between the auricles and ven-
tricles are peculiar forms  of muscular  and tendinous  fibers,
resembling cords and pillars, that are  termed valves, making
a sort of curtain to allow the flow of blood  from the auricles
to the ventricles,  but not in the opposite direction.    At the
 367. Give the essential differences between the auricles and ventricles.  Why does the
left ventricle need the thickest walls?  368. Describe the valves which lie between the
auricles and ventricles. 
20 4
HITCHCOCK'S  ANATOMY
                       point where the arteries are given off
                       from each ventricle are found (in each)
                       three  crescent-shaped  folds of semi-
                       cartilaginous tissue  called Semi-lunar
                       Valves,  to allow the motion of blood in
                       an  outward direction,  but  to prevent
                       the return, which is called regurgita-
                       tion.
                          369.  Pericardium.—In addition to
                       the fasciae and fatty matter which  im-
mediately invest the heart, this organ is enclosed in another mem-
brane in the form of a shut sac,  a fibro- serous membrane called
 Semi-lunar Valves of th
Heart closed.
FiG. 207.
  Semi-lunar Valves of the Aorta laid open, a, Corpus Arantii on the Free Border.  6,
Attached Border,  c, Orifices of Coronary Arteries.
the Pericardium (meaning about the heart).   This contains a
small quantity of a fluid like water, so that the heart actually
floats in a liquid, and does not rest firmly upon any hard sur-
face.   The pericardium not only exists as a  loose  sac  about
the heart,  but it  is reflected upon  it where  the vessels are
given off; covering it in the same manner as  the fasciae cover
and protect the muscles.
   370.  Arteries—Their  Coats.—The Arteries are tough an 1
cylindrical tubes which convey the blood from the heart to the
different parts of the body.  They are made up of three mem-
 Describe the Semi-lunar Valves and their location.  869. What is the sac called that
surrounds the heart ? What fluid does it contain? How much ofit is there?  Is the
pericardium attached at all to the heart?  370. Of how many coats are the arteries com-
posed ? 
AND   PHYSIOLOGY.
205
Fig. 208.
Temporal
  Artery
   Art.
Pediosa.
Arterial System in Man.
Posterior
Tibial
Artery.


Peroneal
Artery.
branes, of which the  middle one deserves especial attention.
This is an elastic coat composed of yellow fibrous tissue (Fig.
209), in order, as we shall presently see, to aid in the circu-
Describe each one and their peculiar value. 
206
HITCHCOCK'S  ANATOMY
joining blood-vessels.  Nerves are distributed to some arteries,
but ordinarily they only accompany them.
   371.  The Aorta,—The  arteries sent to every portion of
 the  body from  the  left  ventricle proceed  from one  trunk,
 called the Aorta, meaning  a starting-point.   It is  nearly an
 inch  in diameter, and  ascends in a perpendicular direction
 for about two inches, when it makes a curve upon itself, and
 descends through  the thorax  and abdomen until it reaches
 the fourth  lumbar vertebra, when, as is the case with most
 of the  large arteries, it divides into  two branches of equal
 size.   Between the curve or arch  of the  aorta  and the heart
 no branches are given off, but from the  summit of this arch
 to the subdivision in the abdomen a great number of branches
 are distributed to the different portions of the  chest and ab-
 domen.

  372. Description  of  Particular  Arteries—Innominata
— Carotid—Subclavian—Axillary—Brachial —Ulnar  Ra-
dial—Palmar  Arch.—The first branch arising from the sum-
mit of  the  aortic arch  is  the  large one called the Innomi-
nata, or nameless artery.   Next comes the Carotid, and both
distribute themselves  to the  head  and  upper extremities.
 371. What is the Aorta? What does the word aorta mean? Give its course till U
subdivides.  Where does it divide into the common iliacs?  372. Whera are the In
nominata Arteries? The Carotid ? 
AND   PHYSIOLOGY.
20*
Fig. 210.
  A View of the Heart, with the Great Vessels of the Neck in Situ.  1, Eight Ventricle
of the Heart.  2, Eight Auricle.  3, Left Ventricle.   4, Left Auricle.  5, Pulmonary
Artery.  6, Arch of the Aorta.  7, Descending Vena Cava at its entrance into the Eight
Auricle.   8, Ascending  Vena Cava.   9, Thoracic Aorta. 10, Arteria Innominata. 11,
Eight Brachio-Cephalic Vein.  12, Left Brachio-Cephalic Vein.  13.  Section of the Sub-
Clavian Artery.  14, Section of the Sub-Clavian Vein.  15, 15, Primitive Carotid Ar-
teries.  16, 16,  Internal Jugular Veins.  17, 17, External .Jugular Veins.  Between
these Veins is seen the  Section of the Sterno-Cleido-Mastoid Muscle.  IS, The Trunk
formed by the Superficial  Cervical  Veins,  known sometimes as the Anterior Jugular
Vein.  19, A Branch from it to the Facial.  20, Main Trunk from the Inferior  Thy-
roid Veins.   21, Superior Thyroid Vein.   22,  Transverse Cervical Artery and Vein.
23, Lingual Artery and Vein.  24, Facial Artery and Vein.

The  Innominata  on  the   right  very soon  becomes  the  Sub-

clavian,  after which the  corresponding  arteries  of both  arms

receive the  same name.    The Sub-clavian  Artery,  as its ety-

mology  implies,  lies   directly   beneath  the clavicle  until  it

reaches the axilla, or  arm-pit,  where it receives  the  name of

                       The Sub-clavian ?  The Axillary ? 
208
HITCHCOCK'S   ANATOMY
Fig. 211.
  A View of the Arteries of the Neck and Shoulder.  1,  Primitive Carotid Artery.  2,
'nternal Carotid Artery.  3, External Carotid Artery.  4, The Superior Thyroid Artery.
5, Branches to the Muscles.  6, Main Branch to the Gland.  7, Inferior Pharyngeal Ar-
tery.  8, Lingual Artery. 9, Facial Artery. 10, Its Branches to the Sub-Maxillary Gland.
11, Sub-Mental Branch.  12, Principal Branch of the Facial as it goes  over the Jaw.
13, Occipital Artery.  14, Branches to the Muscles on the Back of the Neck.  15, Main
Trunk to the  Occiput. 16, Posterior  Auricular Artery.  17, A Branch  cut off, which
goes to the Parotid Gland.  18, Origin of the Internal Maxillary Artery.  19, Origin of
the Temporal Artery.  20, Origin of the Anterior Auricular.  21, The Sub-Clavian. 22,
Origin of the Internal Mammary.  23, Trunk of the Inferior Thyroid, from which arise
in this subject the Anterior and Posterior Cervical Arteries.  24, Branch of tho Inferior
Thyroid going to the Thyroid Gland.  25, Anterior  Cervical going up the Neck. 20,
Posterior or Transverse Cervical.  '27, Branches to the Scaleni and Levator  Scapula?
Muscles.  28, The Superior Scapular Artery.   29, The Thoracica Superior of the  Axil
ary Artery.  30,  A Branch to the Deltoid. 31, Eecurrent Branches of the Intercosta',."

Axillary Artery.    Then as it passes  along the  inner side  of

the humerus it is called the  Brachial, until it has passed  be-

yond the inner side of the  elbow,  where it is divided into the

Ulnar and  Radial,  corresponding in position  and  direction to

               Where are the Brachial, Ulnar, and Eadial Arteries ? 
AND  PHYSIOLOGY.
209
the ulna and radius.   Some-
times, however, the branch-
ing takes place higher up, as
is  seen in  cut 212.   When
these have fairly passed  the
wrist, they both join again in
an  artery  which  describes  a
curve at the base of the meta-
carpus crossing the  palm of
the hand, and called the Pal-
mar Arch.   Small branches
are given off  from  this which
supply the different parts of
the hand,  including the fin-
gers and thumb.
   373. Distribution  of  the
Carotids—Vertebral—Circle
of Willis.—The common Ca-
rotid Arteries,  one  on each
side of the neck, pass upwards
from the innominata and sub-
clavian nearly  as  far  as  the
angle  of the  jaw, when they
divide into the internal and
external  carotids,  the latter
furnishing blood  to the face,
and the former to the brain and
back part of  the  head.   The
Vertebral  Artery is also giv-
en  off from the  sub-clavian,
which, passing  backward,  en-
ters the spinal  column at  the
sixth cervical  vertebra,  and
  Deep-Seated Palmar Arch.  9, The An;
Fig. 212.
  Arteries of the Arm.  1, Termination «(
the Axillary Artery. 2, The Brachial A •
tery.  3, 3, Eadial Artery. 4, 4, Ulnar Ar-
tery.  5, A Eecurrent Branch.  6, Anterior
Interosseous Artery.  7, Superficial Pal-
mar Arch formed by the Ulnar  Artery.  8,
imosis of the two Arteries, much enlarged.
 What is the Palmar Arch ?  373.  Give the branches of the Carotid as it passes up«
ward to the head. 
210            HITCHCOCK'S   ANATOMY

passing through a foramen or opening in the transverse process
of each of these vertebrae, at last reaches  the posterior portion
of the brain.   This  artery in the brain meets with the termi-
nal  branches of  the  internal carotid,  so that the blood  can
easily  reach  the brain  from  either  direction.   By this ar-
rangement, if,  from  pressure or accident, the flow of blood
to the brain in either  of these channels should be  obstructed,
t.ie  other  would  supply it; for  sensation and consciousness
  Circle of Willis.  1, Vertebral Arteries.  2, 3, Anterior and Posterior Spinal Arteries,
4, Posterior Meningeal Artery.  5, Inferior Cerebellar. 6, Basilar.  7, Superior Cerebel
lar.  8, Posterior Cerebral. 9, Branch of Carotid. 10, Internal Carotid.  11, Ophthalmi
Artery. 12,13, Cerebral Arteries.  14, Anterior Communicating Artery.

entirely cease if the brain be deprived of  its  arterial blood.
This arrangement is called the  " Circle  of Willis"  from  its
discoverer.
  What arteries does the Vertebral communicate with in tho brain ?  What is the ser-
vice of this arrangement? 
AND  PHYSIOLOGY.
211
   374.  Thoracic  Aorta—Abdominal  Aorta—Celiac Axis—
Gastric,  Hepatic,  Splenic,  Rencl,  Mesenteric,  and  Lum-
bar  Arteries.—After the aorta fairly commences  its  descent
—called the Thoracic Aorta—several small branches are given
off from it which send nourishment to the heart and lungs, and
next a pair  which are  distributed to  the  diaphragm.   Then
                               Fig.  214.
  A View of the Abdominal Aorta an 1 its Branches.  1, 1, The Diaphragm.  2, Foramen
Quadratum and Section of the Ascending Vena Cava.  3, Foramen Esophageum and
Section of the Esophagus.  4. Foramen Aortienm in the Crura of the Diaphragm.  Tie
Phrenic arteries a t seen  going to the  Diaphragm.  5, Capsulre Eenales. fi, The K: -
neys.  7, Abdominal Aorta.  S, Phrenic Arteries.  9, Coelic—giving off.  10, The Spl.-
nic. 11,'The Oastrie.  12, The Hepatic.  10, Section of Superior Mesenteric.  14,Emr.l-
gent Arteries.  15. Spermatic Arteries.  10, Inferior Mesenteric. 17,17, Lumbar Arteries.
K Division of the Abdominal Aorta.  19. Its last Branch—the Middle Sacral.  20,
Primitive Iliacs.  21, Ureters—in their Position to the Arteries.  22, Internal Iliacs.
23, External Iliacs.  24, Circumflexa llii. 25, Distribution of the Epigastric.  26, Blad-
der distended with Urine. The Vesical Arteries are seen near it.
374. What are the first branches of the Thoracic Aorta? 
212
HITCHCOCK'S   ANATOMY
Fig. 215.
                                    we  meet with a large  trunk
                                    given off just below the  dia-
                                    phragm,  about  half an  inch
                                    in length,  called the Coeliac
                                    Axis, which  gives  origin  to
                                    the  Gastric  artery supplying
                                    the   stomach,  the   Hepatic,
                                    running to the liver, and the
                                    Splenic furnishing  blood for
                                    the  spleen.    Below this we
                                    find the  Renal  arteries, sup-
                                    plying the  kidneys, and the
                                    Superior and Inferior Mesen-
                                    teric  Arteries,   which   givo
                                    blood to the intest'nes, and the
                                    Lumbar Arteries, terminating
                                    in the external muscles of the
                                    abdomen.
                                       375.  Iliac  Arteries—Fe-
                                    moral, Popliteal,  and  Tib-
                                    ial  Arteries —Dorsalis  Pe-
                                    dis.—As  already mentioned,
                                    the  aorta  divides  into  two
                                    branches opposite the  fourth
                                    lumbar   vertebra,   for  the
                                    supply of the lower extrem-
  A Front View of the Femoral Artery, as
well as of the External  and  Primitive
Iliacs of the Eight Side. 1, Primitive Iliac Artery.  2, Internal Iliac  Artery.  3, Exter-
nal Iliac Artery.  4, Epigastric Artery.  5, Circumflexa llii Artery.  6, Arteria Ad Cu-
tem Abdominis.  7, Commencement of the  Femoral just under the Crural Arch. 8,
Point where it passes the Vastus Internus Muscle.  9,  Point where it leaves the Front
of the Thigh to become Popliteal. 10, Muscular Branch to the  Psoas and Iliacus.  11.
External Pudic Artery cut off.  12, Origin of the Internal Circumflex.  13, Profunda Fe-
moris. 14. Muscular Branch.  15, 16, Artery to the Vastus Externus Muscle.  17, Artery
to the Pectineus and Adductors.  18,  First Perforating Artery.  19, 19, Muscular Ar-
teries.  20, 21, Anastomotica.  22, Superior External Articular.  23, Middle Articular
24, Inferior External Articular.  25, Inferior Internal Articular.
  Describe the Coeliac Axis.  Where are the Gastric, Hepatic, Splenic, Eenal, and Lum-
bar Arteries ? 
AND   P II Y S I O L O (J Y .
213
ities.    These  are  the  com-                FlG- 21G-
mon iliacs, from  being near
the  ilium, and  each  of them
soon subdivides into  the Ex-
ternal and Internal Iliac, the
former of which supplies the
greater  portion of  the  leg
w th blood.     As  soon as  it
passes  over  the pubis it be-
comes  the Femoral  Artery,
which at first  is quite exter-
nal,  lying just beneath  the
skin and upon the pubis ;  but
as it passes down the  femur it
plunges deeper and deeper into
the  soft  parts until it appears
behind the knee,  where it re-
ceives the  name of the Pop-
liteal Artery.   This  is only a
few  inches in length,  and  at
the   upper extremity  of  the
tibia divides into the Anterior
and Posterior Tibial Arteries.
The former  runs  along  tho
inner side of the  tibia and
over the tarsal  bones, until it
reaches the metatarsus, when
it becomes the Dorsalis Pedis,
which  gives  off branches   to
Lower End of the same Artery on the Popliteus Muscle.  3, Point of Bifurcation into th«
Posterior Tibial and Peroneal.  4, Superior Internal Articular Artery.  5, Superior Ex-
ternal Articular Artery.  6, Middle Articular Artery.  7, Inferior Internal Articular Ar-
tery.  8, Inferior External Articular Artery.  9, Branch to the Head of the Soleus Mus*
cle.  10, Origin of the Anterior Tibial Artery.  11, Origin of the Posterior Tibial Artery.
12, Point where it passes behind the Annular Ligament to become the Plantar.  13, 14,
15, Muscular Branches. 16, Origin of the Peroneal Artery.  17, 17, Muscular Branches.
IS, 18, AnastomoMsof the Posterior Tibial and Peroneal Arteries near the Heel. 19,
Muscular Branch from tho Anterior Tibial.
  A View of the Arteries on the Back of
the Leg.  The Muscles have been removed
so as to display the Vessels in their whole
length.  1, The Popliteal Artery, cut off
so as to show the Articular Arteries.  2i
 375. What do tho common Iliac  Arteries become as soon as they cross the  pubis?
Giva the lo«ation of the Femoral, Popliteal, Tibial, and Dorsalis Pedis Artery. 
214
II I T C II C O 0 K ' S   ANATOMY
each of the toes,  and supplies the upper part of the foot with
blood.   The Posterior  Tibial  Artery follows  upon the back
side of the leg a corresponding course to  the anterior tibial,
and supplies the sole of the foot and toes with blood.
   376. Capillaries.—The arteries just described area few
only of the principal ones,  since at nearly every inch of their
course larger or smaller vessels are given off according to tl 3
                           Fig. 217.
nature of the part to be supplied with blood, and, with a few
exceptions, such as the  one in the  head  (circle of Willis).
they all terminate in minute vessels called  Capillaries.
  377.  Diameter  of  Capillaries—Functions  Perfori  \
ill  til em.—These are  minute  tubes jloth  to 7-oVotb. of an
inch in diameter, and are always the terminations  of  arteries.
They are of a uniform.size, and very regular in the distribu-

  376. How do nearly all the arteries terminate?  Where  is the only exception ?  877.
State the diameter of the Capillaries. What of their uniformity ? 
AND    PHYSIOLOGY.
215
Fig. 218.
  A Front View of the relative Positions of the Veins and Arteries of the Face and Neck.
Jn the Eight side the Superficial Vessels are seen, and the Deep-seated ones on the Left.
I, Primitive Carotid Arteries.  2, Superior Thyroid Arteries.  3, Internal Jugular Veiia.'
1, External Jugular Veins.  5, A Branch known as the Anterior Jugular Vein.  6, Supc-
perior Thyroid Veins.  7, Facial Arteries.  8, Facial Veins.  9, Zygomatic Branch of tho
Facial  Artery.   10, Nasal Branch  of the Facial Vein.   11, Anastomosis of the Facial
Artery and Vein with the Ophthalmic Artery.  12, Venous Arch above  the Nose.  13,
Frontal Vein.  14, Temporal Vein.  15, Temporal Artery.   16, Frontal Branches of
the Temporal Artery and Vein.  17, Infra-Orbitar Vessels.  18, Sub-Aponeurotic Branch
pf the Temporal Vein.   19, 20, Venous  Anastomosis around tho Eye-Lids.  21, Frontal
Branches of the Ophthalmic Vessels of Willis.
                                     10 
216
HITCHCOCK'S   A N A T O M V
Fig. 219.
tion of  their branches, without any increase in  their diam-
eter.   The only exception to this is where red blood is not re-
                                   quired for the nourishment of
                                   the parts;  as in the white of
                                   the eye, the  finger nails,  the
                                   tendons,  etc., where  the  ca-
                                   pillaries are too small to allow
                                   the corpuscles of blood to pass
                                   through them.   And yet in
                                   many of the capillaries we find
                                   their  size to be so small  that
                                   the corpuscles could not,  if
                                   unyielding,    pass   through.
                                   But  this is  readily  accom-
                                   plished in most  cases by the
                                   flexibility of the corpuscle,
                                   which  permits   itself  to be
                                   doubled up  to such an extent
                                   that it will easily pass through
                                   a  tube much smaller than its
                                   normal diameter.   In  the ca-
                                   pillaries  the  important  pro-
                                   cesses of secretion, nutrition,
                                   and the  production of  a  por-
                                   tion of animal heat take place  ;
                                   so that  there is  no place in
                                   the  whole  body except  the
  A View of the Veins of the Trunk and    outer COat of the eye, tile ten-
Neck.  1, The Descending Vena Cava. 2,    ,        •■       .,       -,    ,.
The Left Vena Innominata. 3, The Eight    donS,  the  nails,  and white
Vena Innominata. 4, The Eight Sub-Cla-    portions  of  the  body gener-
Vian Vein.   5, The Internal Jugular Vein.    r                    . ~  P
6 The External Jugular.  7, The Anterior    ally where true Capillaries are
Jrgular 8, The  Inferior Vena Cava. 9    not found.
The External Iliac Vein.  10, The Internal
Iliac Vein.   11, The Primitive Iliac Veins.
12, 12, Lumbar Veins.  13, The  Right Spermatic Vein.  14, The Left Spermatic Vein.
15, The Eight Emulgent Vein.  16, The Trunk of the Hepatic Veins.  17, The Vena Azy-
gos. 18, The Hemi-Azygos. 19, A Branch communicating with the Left  Renal  Vein.
20, The Termination of the Hemi-Azygos in the Vena Azygos.  21, The Superior  Inter-
Costal Vein.
Where are true capillaries not found ?  What takes place in them ? 
AND  PHYSIOLOGY.      •        217
Fig. 220.
   378. The Veins—Their Coats—Their Volume.—The Veins
carry the blood from all parts of the body to the heart.  Like
the arteries, they have three coats, and the larger veins follow
the same general course as  the  large  arteries.   The smaller
veins,  however, are much more numerous than the smaller ar-
teries, and are  most abundant just  beneath  the skin.  The
whole  volume of the veins may be regarded as  a large cone,
 * th the base at the surface of the body jand  the apex at the
fc-'art,  so that in these vessels the blood is continually  flowing
faster  and faster, in  consequence of the  fluid coming  into a
larger channel from small extremities, while the reverse hap-
pens in the arteries.   The veins arc much thinner  in  struo
ture than the arteries, so that after  death  they most  usually
collapse.   (See Fig. 218, p.  215.)
   379. Location of the larg-
er  Veins—Sinuses.—As  al-
ready mentioned, the larger
veins  usually  lie   near the
larger arteries.   Both  also
frequently   have  the   same
names.  But  there are  sev-
eral remarkable exceptions  to
this,  as  in the vessels  of the
brain.  Here   are  but  few
veins, but  several  sinuses  or
channels.   These are  canals
excavated in the  dura mater
of the brain with this  mem-
brane for  an  outer coat, and
the serous  layer of the true
v nns for an inner coat.  These
run in different directions on
the inside  of the skull, and
  Sinuses of the Base of the Skull.  1,
Ophthalmic Veins.  2, Cavernous Sinus.
3, Circular.  4, 6, Inferior Petrosal. 5, 9,
Occipital Sinuses.  7, Internal  Jugular
Vein.
 378. What course does the blood take in the veins ?  Give the coa:s of the veins.
What is the relative proportion of small veins and small arteries?  What is said of their
aggregate volume ? 379. Where are the larger veins usually found ? What are Sinuses,
and where are they found ? 
218
( T CHCOCK'S
ttiost of 'bcir empty into  the great veins of the neck.   Their
)robable service is to afford a free passage of blood  from the
ir _in, even if by excess of arterial action this organ  should be
Jvercharged  with blood.
  380.  Portal   System—Use of the  Portal  System.—An-
other apparent exception  to  the ordinary system of veins  i3
ueen in  what is  called the  Portal System.  This comprises
those vessels which receive their blood from  the  intestinal
canal, the stomach, and  the spleen.   As these small vessels
unite into  a larger  trunk,  instead of passing directly to the
heart, they form what is  called the Portal Vein, which  emp-
ties itself into the  liver.   This vein  ramifies into every part
of the liver,  where the blood is again collected  by a series of
vessels which unite  into  several  trunks, called  the Hepatic
Veins, and which convey  the blood to the heart.   The design
of this arrangement is not  certainly  known as  yet, although
it is probable that the blood  which returns from  the alimentary
canal is not  fitted to enter the general circulation until it has
gone through some change in the liver.
           fig. 221.                381.  Origin  of  the Veins
             "                  —Valves—Their Discoverer.
                                —The Veins all take their ori-
                                gin in the capillary  vessels in
                                every part of the body except
                                those of  the  stomach, and in
                                number  and length of tube
                                greatly  exceed  the  vessels of
                                the  arterial system.  In the
                                lining membrane of the veins,
                                also,  we  find  a  peculiarity
                                not presented  in the arteries.
                                This is the presence  of  folds,
                                so that pouches or bags are
formed, which  readily suffer the flow of blood towards the
  Of what especial service are they ? 380. Describe the Portal System.  What is the
probable use of so marked an exception to the general circulating System ? 381. Whera
do the Veins take their origin ?  What is said of the Valves of the Veins ?
 Vein laid open to show the Valves,  a,
Vein.  6, Valves. 
AND   PHYSIOLCvtT.
2*9
Fig. 22-2.
heart, but almost entirely pre-
vent its  passage in an oppo-
site direction.    They  act in
the same manner as valves in
machinery, although with  no
loss from friction,  and  conse-
quently  no necessity  of a lu-
bricating fluid.    It  was the
discovery  of these valves in
the veins which  led  Harvey,
an English  physician,  to the
greater  discovery  of the  cir-
culation of the blood.    He in-
ferred that  the  blood  could
pass  in   but  one  direction
through the veins, and conse-
quently in the opposite direc-
tion through the arteries.
    382.  Inosculation — Use
of Anastomosis.—The arter-
ies  and veins open into  each
other (i. e., their own vessels)
very  frequently, allowing  a
ready flow of blood  from one
vessel to the other, even if the
flow does not happen to be in the
most  favorable direction  from
the center of circulation to the
                                     The Superficial  Veins on the Front of
the Upper Extremity.  1, Axillary Artery. 2, Axillary  Vein.  3, Basilic Vein where
it enters the Axillary.  4, 4, Portion of the Basilic Vein which passes under tho Brachial
Fascia—a portion of the Vein is freed from the Fascia. 5, Point where the Median Ba.
silic joins the Basilic Vein. 6, Points to the Posterior Basilic Vein. 8, Anterior BasilU
Vein. 9, Point where the Cephalic enters the Axillary Vein.  10, A portion of the sam»
Vein as seen under the Fascia; the rest is freed  from it.  11, Point where the Median
Cephalic enters the Cephalic Vein.  12, Lower portion of the Cephalic Vein.  13, Median
Cephalic Vein. 14, Median Vein.  15, Anastomosing Branch of the Deep and Superficial
Veins of the Arm. 16, Cephalica-Pollicis Vein.  17, Sub-Cutaneous Veins of the Fin-
gers.  18, Sub-Cutaneous Palmar Veins.
Who discovered the circulation of the blood? 
220           HITCHCOCK'S  ANATOMY
Fl_. 223.
  The Arteries and Deep-seated Veins on
the Back of the Leg.  1, Popliteal Vein.
2, Popliteal Artery. 3, 4, Vein and Artery
in their relative Position  on the Back of
the Knee-Joint. 5, Popliteal Vein on the
inner Side of the Joint.  6, Popliteal Ar-
tery without and beneath it. 7, Extremity
of Saphena Minor Vein.  8, 9, Internal Ar-
ticular Vessels, both Arteries and Veins.
teries and Veins.  12, Junction of the Pen
ous Branch from the Anterior Tibial  Vein.
Anterior Tibial Artery comingthrough the
Artery. 17, Its two VensB Comites.  13,  I
20, Vessels on the Heel.
  extremities.   This relation of
  parts is called Inosculation or
  Anastomosis.   This  arrange-
  ment gives a plentiful supply
  of blood to every part  of the
  body, if, by wound or pressure,
  the ordinary channel of blood
  to  any  part  should  be  ob-
  structed or  completely closed
  up.     Inosculation  is  moso
  abundant in the veins and su-
  perficial arteries,  since these
  are most liable to be thus im-
  peded.
     383.  The Blood — Micro-
  scopic   Structure — Plasma
  or Serum—Red Corpuscles—
  White  Corpuscles—Propor-
  tion  of  one  to the  other —
  The blood of the human sys-
  tem amounts to about eighteen
  pounds, or nearly  ten quarts.
  Is has a specific gravity a lit-
  tle greater than that of water,
  is of a bright  scarlet color if
  drawn from an artery, or dark
  purple if taken from a vein,
  with a taste slightly alkaline,
  and an odor resembling that
10, 11, External Articular Vessels, both A--
>neal and Posterior Tibial Veins.  13, A Ve -
  11, A Vein from  the Gastrocnemius. 15,
Interosseous Ligament.  16,  Posterior Tibial
'eroneal Artery.  19, Its two Venae Comites.
  3S2. What is meant by Inosculation or Anastomosis ?  What is the service of anasto-
mosis?  In what vessels is it most abundant?  3S3. IIow much blood is there in a 2m«
mar» adult?  State its color and odor. 
AND  PHYSIOLOGY
221
Crystals from Human Blood.
of the breath of the ani-                 Fig. 224.
mal  from which  it  is
taken.     It   penetrates
every solid tissue of tl e
system, as may be known
by puncturing any part
of the body with  even a
pin,  when blood  is  sure
to follow.   If it  be  ex-
amined  with  a   micro-
scope    when    freshly
drawn,  it appears to  be
made up of a transparent
liquid called the  Serum
or Plasma,  and a num-
ber of minute circular bodies,  mostly of a  red color, called
corpuscles,  or  minute  bodies.   This fluid is found, on analy-
sis, to be made up of water, albumen, fibrin, and several salts,
some of which are found  in crystals,  as is seen in the cut.
After it has been drawn  from the body a considerable time, it
separates into  a thickened  mass called Coagulum,  made up of
       Fig. 225.         fibrin and the  corpuscles,  while  the
                       serum with the albumen still remains
                       as  a transparent  liquid.   The  Red
                       Corpuscles prove to bj flattened discs
                       with both  surfaces  slightly concave,
                       and  measuring  about   __-Voth of an
                       inch in diameter, and  are  in  reality
                       nothing but  a  cell, that is a bag or
                        sac containing a fluid composed of the
                        two  proximate principles globuline and
hematine.  Besides the  red corpuscles, there   exists another
kind in  the blood known as the White  or  Colorless Corpus-
cles.   They are by no means so  abundant, when the body is
  What is its appearance under the microscope ?  How does it conduct itself after stand-
ing a while in an open vessel?  Describe the Red Corpuscles.  Describe the White Cor-
puscles.
  Red Corpuscles of Human
Blood,  a, Seen on the Surface.
c, Seen in Profile,  b, Seen in
a Roll Magnified 400 Diameters. 
222
HITCHCOCK'S  ANATOMY
in health, as the red corpuscles.  But in certain diseases, and
especially if there be a wound in any part of the  body to be
healed,  the white corpuscles  are developed  at  a great rate,
although their abundance ceases when the  system is restored
to a sound  state again.   Their  average diameter  is  nearly
soVoth  of an inch, and they appear to be nucleated cells.  The
proportion of the white to the red corpuscles in health is nearly
a i 1 to  346.   The whole amount of blood corpuscles has been
estimated as  high as 65,570,000,^00,000.

   384.  Effect  of an Alternate Exposure  to  Oxygen  and
Carbonic Aeid.—If the  red corpuscles are alternately exposed
to oxygen and  carbonic acid  they lose their circular form,
and become corrugated or star-shaped, and finally are destroyed;
and it is calculated that  millions of these corpuscles are  de-
stroyed at each pulsation of the heart.
        FUNCTIONS  OF  THE  CIRCULATORY  SYSTEM.

  385.  The  Main Use  of the Blood-Vessels—The large
Angle  made by the  Arterial  Branches near  the  Heart.—
The first and most obvious use of the blood-vessels is to allow
a free and rapid passage of  this  fluid to every part of the
body.   This is evident from the smooth  lining  of all the ar-
teries and veins, and from the fact that, with the exception of
the large arteries near the heart, the vessels  branch off  at  a
small angle  from each  other,  which  arrangement offers the
least possible obstruction to the passage of the blood.   In the
organs near the heart, as the  head and lungs,  the  blood would
readily  pass by smaller vessels  and by less force of the heart
in sufficient quantity.  But in that case  the parts of the  body
quite distant from the center  of circulation of the  blood would

  When are the white ones the most abundant?  State the approximate number of blood
corpuscles in one individual.  3S4. What effect has an alternate exposure of oxygen and
carbonic acid upon these ? How many are possibly destroyed at each pulsation of th«
heart ?  385. Give the use of the arteries and veins. 
AND  PHYSIOLOGY.
223
be  imperfectly  supplied.   And  apoplexies  and  congestions
would be much more frequent than they now are in tho vital
organs,  if the arteries  did not  branch off at nearly a right
angle.
   386.  Why  a   large  Amount  of Arteries and  Veins.—
The necessity for such a large amount of arteries and veins,
and thair  numerous connections with each  other, is evident
f om the  great  variety  and  extent of the  tissues,  and also
from the great liability to obstruction from inflammations, ac-
cidents, or even the ordinary compression of clothing.   But
arranged as these vessels are in the body, it  is a very difficult
thing by any mechanical means entirely to check the flow of
blood to any part.   But were it not for this  system of ample
inosculation the amputation of a portion of the body would
generally produce fatal results.
   387. Comparative Capacity  of  the Arteries  and Veins,
—If all the arteries in the body  were  to be made into a singld
vessel,  the capacity of it would be much less than that of a
similar vessel made by the union of all the  veins.   This  dif-
ference in capacity will in part result from  the feebler char-
acter of the forces which propel  the blood  through the veins
than through the  arteries,  and consequently venous obstruc-
tion could not  be  so easily overcome as  if it were in the ar-
teries ; and in order to  compensate for deficiency in power, an
increased  amount of tubing is provided.
    388. Forces  of  the  Arterial Circulation.—The inquiry
naturally  arises, What are  the forces that send the blood
through the circulatory channels ?
    389.  Contraction of the Heart—Elasticity of the Mid-
 He  Coat.—In  the  first place the contraction of the heart  i_
 the most essential force in driving the  blood outwards.  This
 force has  been  estimated  at thirteen pounds,  though the re-

   Why do the arteries near the heart branch off at a large angle ? 386. Why is there *o
 lar-e an amount of arteries and veins ?  387. What is the comparative capacity of the
 veins and the arteries ? 358. What are the forces of the circulation ? 389. What is said
 of the contraction of the heart ?  What is the estimate of the force that it exerts ?
                             10* 
 224           HITCHCOCK'S  ANATOMY

 suit can not be relied on for perfect accuracy; and that this is
 no inconsiderable force may be inferred from the great amount
 of resistance that is offered to this current from  the ramifica-
 tions of the smaller arteries,  whereby the velocity is increased
 as well as the surface of resistance.  It may also be seen by
 wounding an artery of medium size, when the  blood is sent
 out in jets,  and  sometimes  to the distance of several  feet.
 This,  however,  is not  the whole  amount of the propulsive
 force in the  arterial system,  for the middle or elastic coat as-
 sists by a secondary action.   When the ventricle contracts or
 the  heart beats,  the blood is driven into the  aorta  and its
 larger branches with so much force, that the middle coat yields
 considerably, and the artery is distended  beyond  its ordinary
 size.   As soon as the contraction of the ventricle ceases, of
 course the blood is forced back towards the heart by the elas-
 ticity of the  artery.  But as soon as it commences to flow to-
 wards the heart the semi-lunar valves close at once, prevent-
 ing the flow  in that direction, so that the whole  force of the
 artery is expended in driving the blood towards the extremities.
   390. Pressure  of  the  Muscles.—Another power  which
 aids in the propulsion of the arterial blood is the pressure of
 the muscles upon the arteries.   This is effected  by the en-
 largement which always takes place in the belly of the mus-
 cle whenever it is used.   This is not a constant power, acting
 only during exercise of the muscles.
   391. Forces of the  Venous  Circulation.—The  agencies
by which  the blood is returned  to  the heart  are  not  so well
known  as  those  just  considered.   The valves in the lining
membrane of the  veins  seem to be a contrivance to supply the
 sleficiency of power to drive the  blood back.
   392.  Pressure of  the  Muscles.—The  pressure  of  the
 muscles, without  doubt,  is  another important  impulse in

 When can the forces of the circulation in arteries be well seen? How does the mid-
dle coat assist in this work? Of what use are the semi-lunar valves? 390. How does
the pressure of the muscles aid in the circulation? 391. How do the valves aid in the
venous circulation ?  392. Does muscular pressure aid in this? 
AND  PHYSIOLOGY.
225
aiding the return of blood towards the heart.   For, as in the
aorta, its elasticity forces the blood, first  against  the semi-
lunar valves and then  onwards  through the  arteries, so the
muscles, pressing upon  the  veins, urge  the blood into the
pouches or valves on  their  inner coat, which, preventing re-
gurgitation, assist  in returning it towards the heart.
   393.  Respiration.—Respiration  is  another  cause  that
greatly aids in emptying the  veins.   In some persons a dis-
tinct fullness or pulsation of  one of the veins of the neck  is
noticed during each  inspiration.   This is produced  by the
partial vacuum made by the act of inhaling air ;  that  is, as a
pressure is produced on all parts of the body by the atmos-
phere, not only a rush of air  is made into the mouth,  but the
blood is  forced into the heart by  the same cause.   And  could
we examine all the large veins of the body during inspiration,
without doubt  we should see the blood returning  rapidly in
them at each inhalation of air.
   394. Affinity of Venous  Blood  for  Oxygen.-The affinity
or desire of venous blood for  the  oxygen, and the arterial  for
the  tissues, are important  causes in  the  circulation,  and  es-
pecially in the capillaries.   It is a principle well known  in
physics, that if two fluids of  different degrees of affinity for a
third fluid meet each other in a capillary tube, the  fluid hav-
ing  the strongest affinity for the third substance  will either
partially or wholly force out  the other fluid.   This  takes place
equally well through porous  substances, membranes,  or  capil-
lary tubes.
   395. So that when pure air is present upon one  side  of the
membrane of  the lungs  and venous blood  on the other, the
latter u-ges itself onward to  meet the oxygen, and  thus  forces'
that which is already  purified into the pulmonary vessels, and
thence into the heart.
   396. The same  thing is seen  in the capillaries  of the  e*~

  393. How does the respiratory act aid the  circulation of the blood ?  394. How doe.
chemical affinity aid in the circulation ? 
2 20            HITCHCOCK'S   ANATOMY

tremities,  where  the arterial  blood,  by its affinity for the
healthy tissues, forces along that which is already surcharged
with carbonic acid into the systemic veins.
   397. Forces  of the  whole  Circulation.—The forces, then,
which  propel the blood through the whole system may be thus
briefly summed up :
               1. Contraction of the heart.
               2. Elasticity of the arteries.
               3. Capillary force.
               4. Muscular pressure.
               5. Act of inspiration.
               6. Arterialization of the blood.
   398. Course of  the Blood  through  the Body.—As  al-
ready  mentioned, the  ventricles  are the propelling  and the
auricles the receiving cavities.   Hence, in tracing the course
of the blood  through  the  body,  beginning with  the  left ven-
tricle,  we find the current  passing through  the  aorta and  ar-
teries  to all parts of the body except the lungs.   As soon as
it has  gone through  the capillaries it returns to the right au-
ricle by the different veins, from which cavity it passes to the
right ventricle, and thence to the lungs.   After it has received
its due supply of oxygen, it is  received by the left auricle,
from which it passes again to  the whole system.   The  parts
of this circle and their order are as follows  : left ventricle, ar-
teries, capillaries, veins, right  auricle, right ventricle, lungs,
and left auricle.  Thus we see that the whole  circulation iu
man and  all  mammalia  follows  through  the body  a course
represented by the figure 8.
   399.  Relative Time Occupied   by  Contraction  of  Au-
 ricles and  Ventricles.—The diastole or dilatation of auricles
■and ventricles occupies a longer  period of time  than  the cor-
 responding systole,  or contraction.   If  we divide  the  whole

   897. Give a synopsis of the circulatory forces.  398. Give the course  taken by the
 blood as it circulates through the body.  By what figure may it be represented ?  ■'•'.>%
 What is the systole and diastole of the heart ? 
AND   PHYSIOLOGY.
227
,/'							1
				<:;;		...--	...---
Auricles.
Ventricles.
  Diagram showing the relative Time occu-
pied by the Contraction of the Auricles and
Ventricles, the converging lines from left to
right indicating the contraction, and the  di-
verging ones the dilatation.
portion of time occupied by one pulsation into eight intervals,
we shall find that  the auricles employ only one of these in-
tervals in contraction, and the remaining seven by dilatation;
while the time occupied by the         Fig. 226.
contration of the ventricles  is   ' 2  3  +  5  e  7  °
the same as their dilatation, as
may be seen in the diagram.
   400. The   Sounds   of  the
Heart—Cause of the First
and Second  Sound.—If the
ear be applied over the heart
of  a   healthy  person,  two
sounds will  be  heard,  one
of which corresponds in time
with   the  pulsation   noticed
at  the wrist, or  any other
large  artery  of  the body.
These sounds  do not corre-
spond  to each other  in  intensity or duration, but are some-
what indefinitely represented by the sounds given to the mono-
syllables  " lub" and "dup:"  the  first a  long  and heavy
sound, and the second a  short and light one.   The first sound
is undoubtedly caused by  the contraction of the  heart,  the
rush of blood, and the impulse of the organ  against the side
of the  chest; while  the second is the clicking  of the semi-
lunar valves as they close at the commencement of the  aorta
after the ventricular contraction.   That the  last sound is due
to this cause is proved by an experiment performed on a dog,
of introducing a hook through  the aorta, and holding back one
of these valves, when the second sound entirely failed.
   401. Number of  Pulsations  per  Minute.—The   number
ck pulsations of the heart varies  considerably at  different  pe-
riods  of life.   Thus  the following table  shows the  average
number of pulsations  each minute at different ages :
  Give the relative time occupied by the contraction and dilatation of the auricles and
ventricles. 400. What two sounds are  made at each complete  pulsation of th? hea-t?
Give the causes of the first sound.  What is the last sound owing to?  What proo' vi
it? 
228
HITCHCOCK'S   ANATOMY
          New-born infant....................130   to  140
          During the 1st year..................115   "  130
                "  2d  "  .................100   "  115
          From the 7th to the 14th year........ 80   <;  90
             "   14th  "  21st  "  .......75   "  85
             "   21st  "  60th  ,:  ........ 70   "  75
          Old age........................... 75   "  80
   402.  Causes  affecting  the  Pulsations.—Muscular exer-
tion has a considerable influence upon the rapidity of the con-
traction of the heart.  So  also  has the position of the body.
whether sitting,  lying,  or  standing.   The  time of  day or
night likewise has  an important influence, the highest number
of pulsations being  found  at noon,  and the fewest  at mid-
night.
   403.  Use of  the  Corpuscles.—The function  of the Red
Corpuscles seems to be  to convey oxygen to the tissues,  and
as this is the agent which is continually promoting the change
or waste of the system, these corpuscles  seem to be the great
agents for disassimilating the tissues and  the blood itself. The
colorless or white corpuscles seem to  be the agents by which
the repair of the body is effected,  since they  are  greatly aug-
mented in number when there is a large  wound to  be  healed,
or when there is  a great amount  of internal  or  external in-
flammation.
   403a.  Statistics.—In an ordinary life of a man the heart
beats at least 3,000,000,000 times, and propels  through the
aorta one half a  million tons  of blood.


               HYGIENIC   INFERENCES.

   404.  But  few  Diseases  of  the  Circulatory Organs.—
1. Though the blood-vessels  are so constantly in use,  and so
easily excited by every muscular movement and  mental emo-
tion, yet they are  affected  by only a few diseases, and many
  401. State the number of pulsations of the heart at different periods of life.  402. What
causes modify the number of the pulsations?  403. What is the probable business of the
Red Corpuscles?  What of the White? 404. Are there many diseases of the Circulatory
organs? 
AND  PHYSIOLOGY.
229
of these affections, which seem to be diseases of the heart, are
merely  sympathetic, and the difficulty lies in other organs.
  405.  Avoidance  of sudden  Efforts.—2. But those per-
sons who have  a tendency to diseases  of  the heart,  sympa-
thetic or  organic, should be  on their  guard against  sudden
exertions, and, to as great an extent as  possible, avoid mental
anxiety and alarms.   Heart diseases are most common late in
life, at  or about sixty years of age.
   406.  Principal  Danger  from  Wounds—Treatment of
Wounds of Arteries.—3. The principal danger  to  be feared
from these organs results from wounds.  If these are in the
arteries, they require prompt attention, but if in the veins,
they need scarcely ever excite fear.  If an artery be wounded
—which can always be known by the escape of blood in jets,
and not a steady stream—the wound should be either closed,
or the artery pressed upon between the wound and  the  heart
with so much force as to stop the flow of blood through it.
In case of any such arterial wound it will always  be well to
tie a bandage as tight as  possible immediately over the wound,
and then compress  the artery as already mentioned.   If the
wound  be on the hand or forearm, the brachial artery may be
found and compressed just above the inner angle of the elbow.
Or if it is desirable to compress the artery still higher up, the
axillary artery  may be found in the armpit, where by pressing
outwards, nearly all the blood flowing to  the  arm  may be
checked.
   407.  Method of  Checking  the Blood  to the Lower Ex-
tremities .-4. If it is desired to check the flow of blood to the
lower extremity,  the  popliteal  artery lies directly against the
femur  upon  the backside of the knee-joint, where a comprer
sion of it may be effected with great advantage.   Nearer tl j
heart  (in the  groin)  the  femoral  artery is found, where  it

  405. What should those persons predisposed to these diseases especially be on theii
 cvtard a-ainst?  At what time of life are Heart diseases the most frequent?  406. How
 can we distinguish between the wound  of a vein and that of an artery?  How may ar-
 terial hemorrhage be most readily checked in the upper extremities? 40T. How may il
 be checked in the lower extremities ? 
230
HITCHCOCK'S  ANATOMY
crosses the os innominatum lying just beneath the skin. Here
an efficient compression  may be made,  since all the anterior
part of the thigh and the whole of the leg proper, is supplied
with blood from  this artery.
  408. 5. Except bad wounds, however,  a tightly drawn band-
age, directly over the wound, thoroughly wet with cold water,
will check  hemorrhage  sufficiently, until a surgeon  can be
called.
COMPARATIVE ANGIOLOGY.
  409.  Heart  of Mammals.—In all mammals  the heart  is
                                divided into four cavities,  as
            Fig. 227.             in man. Its form, however, is
                                more rounded and  less elon-
                                gated.   In one species of the
                                whale this organ is  cleft in a
                                peculiar manner, the division
                                between  the  two  ventricles
                                being indicated externally by
                                a deep fissure in its apex.  In
                                the  Ox,  Hog,   Sheep, and
                                Goat there are always  found
                               one  or two  bones  in  the di-
                               visions between   the  ventri-
                               cles.    En  most  mammals it
                               is placed more in  a right line
 Circulation in Man. a. Right Auricle.   with the  middle of the body,
I. Right Ventricle,  c. Left Auricle. _.   an(J  not   SQ  obliquely  a8  in
Left Ventricle, e. Aorta.  / Vena Cava.                     -1  J
g.  Pulmonary Artery.  h.  Pulmonary   man.
Veins.
 403. What treatment will check all ordinary hemorrhages? 409. What is peculiar ir
the heart of the Whale, the Ox, the Sheep, and Goat?  Where is tho heart located ir
quadrupeds ? 
AND  PHYSIOLOGY.
231
   410. Aorta  and Pulmonary Veins.—The manner in which
the Aorta and its branches are given off varies greatly in these
animals, as may be seen by the cut.   The number of Pulmo-
  FlG. 228.
D        E
2 3
F

  3
^  \U^
a     b   a    b  a    b  a   b   a    b   a    b
  Diagram of the Principal Varieties of the Aorta in its Principal Branches in a, Man ;
 b, Elephant  c, Cetacea; d, Bat; e, Carnivora; f. Seal; g, Ruminants; n, Reptiles.
 1, Right Subclavian.  2, Right Carotid. 3, Left Carotid.  4, Left Subclavian. 5, Verte-
 bral,  a, Ascending and b Descending Aorta.

 nary Veins varies upon  the different  sides of the body,  and
 is  generally according  to the  number of lobes in the lungs,
 the relations  of the sides being represented by the  formula
 3 + 2.
   411.  Economy of  Diving Animals.—In diving animals the
 vena cava is capable of great dilatation, in order to contain an
 unusual quantity of blood which accumulates there when the
 animal suspends respiration under water,  since  it can not be
 purified except  in the lungs.  Still further protection to the
 heart in diving;  animals is  seen in the vena cava ascendens,
               <_>                                              *
 where a circular muscle, by its contraction, can completely cut
 off the flow of blood to the heart
 from the lower extremities.
   412.  Blood Corpuscles of
 Ihmmals—Wonder   Nets.—
   The blood of  mammals, for
 the  most part, presents  small
 round, disc-shaped corpuscles,
 similar to, but smaller than those in man.
Fig. 229.
<_$*
m
     B                 A
  Red Corpuscles of the Ox.  A, In their
Natural State,  a, Seen in Profile, b, Sc?n
on the Surface.  B, Altered Corpuscles.
            This is especially
 410. What is peculiar about the aorta and pulmonary veins in many mammals?  413.
What is the arrangement of the vena in diving animals? 
232
HITCHCOCK'S  ANATOMY
 true of ruminants.  The largest animals, such as the elephant,
 have very small corpuscles.   In some of the camels and llamas
 the corpuscles are large and somewhat elongated.   The same
                                     is true of the dromedary.
                                     Crystalline   substances
                                     are  found in the blood
                                     of  other   mammals  as
                                     well  as man.   The a, *
                                     nexed cut shows crystals
                                     from the  blood of the
                                     Guinea pig.
                                       The  distribution  ot
                                     the arteries  of  quadru-
                                     peds is a subject of con-
                                     siderable  interest.   In
                                     grazing animals,  which
     Blood Crystals of the Guinea Pig.        hold their heads low, in
 addition to large arterial trunks, we find a great number <.f
 very small ones, which are exceedingly tortuous in their course,
 called  " Wonder Nets."   This arrangement is to prevent atoo
 rapid flow of blood to the head by the force of gravity,  which
 would of necessity take place when the head is  so constantly
 in a dependent position.   A similar disposition  is  seen  in the
 limbs of the sloth and other animals which are  like  them in
 tardiness of movement.   In  the fore-leg of the  lion,  where
 great muscular force is exerted, the main artery passes through
 a perforation in the  bone, so as to secure  it from  obstruction
 to the  flow of blood by pressure of the rigid muscles.
   413. Heart of  Birds.—The heart of birds is highly mus-
cular and of very large size in proportion  to  the bulk  of the
body, and in general structure resembles  the same organ i.i
mammals.   The valves of the right ventricles, however, are
supplied with a strong band of muscular  fibers, which gives
 412. What is peculiar about the blood  discs or corpuscles of the larger animals?
What is the form of nearly all of them?  In what animals are they oval? What are
Wonder Nets, and why are they introduced ?  413. What is worthy of note with refer-
ence to the heart of birds ? 
AND   PHYSIOLOGY.                  233
additional impulse to the blood as it  is forced into the  pulmo-
nary arteries    The need of this arrangement is to give a full
supply of blood to the  lungs, which  the  ordinary powers of
the heart could not effect.
                                Fig. 231.
08                   Cl
      Arterial System of a Bird.
  Arteries of the Gr;be.  a, Aorta   am, One of its large Branches.  It gives off t  «
Carotid (ac) and Subclavian, is ultimately distributed to the muscles of the chest, and
corresponds to the mammary arteries of mammals, av, One of the Branches of the
Vertebral Artery supplying the Muscles of the Shoulder,  ce, Arterial Loops formed by
the Branches of the External Carotid,  al. Lingual Artery,  t, Trachea, or wind-pipe.
ar. Renal Arteries,  ai, Ischiatic  Artery proceeding to the lower extremities,  as, Sac-
ral Artery, forming a continuation of the Aorta, anil giving origin to the Inferior Mesen-
teric Artery, etc.  cl. The Cloaca.
Why ao the valves have an especial muscle ? 
234
HITCHCOCK'S  ANATOMY
Fig. 232.
   414.  Arteries—Wonder .lets.—The trunk of the  aorta is
very short, and after giving arteries to supply the heart it di-
vides at once  into two large branches, quite unlike the con-
formation in  mammalia.   Wonder nets, too, are often  found
in birds, and especially in those arteries supplying the brain,
eyes and legs.
                                    415.  Blood.—The blood of
                                  birds  has  the  highest  tem-
                                  perature  of  the   vertebrate
                                  animals—110° F.   The blood
                                  cells,  or corpuscles,  are  al-
                                  ways of an elliptical form and
                                  of a very uniform diameter.
                                    416.  Heart  of  Reptiles.—
The heart of reptiles ordinarily consists of a single ventricle,
            Fig. 233.                        Fig. 234.
®
®
  Pigeon's Blood (red) Corpuscles Magni-
fied 400 Diameters. A, In Natural State.
B, Altered by Acetic Acid.
                              Blood Corpuscles of the Frog, 40ii Diameters.
                             A, In Serum, a. Fully Developed,  b, Nucleus
                             with clear contents.
                            or propelling cavity, and two  auri-
                            cles, or receiving  cavities, so that
  Circulation in Reptiles,  a, Heart, the  pure  blood  is  mixed with  the
b, ventricle,  c, c, Auricles.       impure (or  a portion  of it)  as it
comes from the lungs, which accounts in part for  the general
sluggishness of these animals.   The  blood corpuscles of rep-
tiles are large and oval, as may be seen in Fig. 234.

  414. Into how many branches does the aorta at once divide ? Where are wonder nets
found in birds?  415. What is said of the temperature of birds ?  What of blood-cells?
416. Describe the heart of reptiles.  What is tho effect upon the blood? What is the
size of their blood-vessels? 
AND   PHYSIOLOGY
   417.  Blood-Vessels.—The  arrangement of  Blood-Vessels
is very diverse, since one portion of them breathe by gills and
another by lungs, while frogs in their early condition are fur-

                              FiG. 235.
Carotid
\rtery.
Arches of ^
the Aorta, ^v
Kidneys. -
Ventral
Aorta.
Intestines.
Circulatory Apparatus in the Lizard.
417. Why are blood-vessels arranged differently in many of the reptiles ? 
!J6
HITCHCOCK'S  ANATOMY
up

vd
ad
vp
oo
nished with the former, but in adult age, after passing through
a metamorphosis, have the latter system of respiratory vessels.
           Fig. 236.                 418. Heart  of  Crocodile.
                                 —Crocodiles and turtles ex-
                                 hibit the most perfect form of
                                 heart, for it agrees essentially
                                 with  that of mammals, as may
                                 be seen in Figs  236 and 237
                                 But  there  is a small opening
                                 just at the  outlet of the  two
                                 ventricles,  so that  the  pure
                                 and impure blood is mixed.
                                    419.   Portal   System.-
                                 Reptiles  have a double Portal
                                 System,  one  set  of  vessels
supplying the kidneys and another the liver.
   420.  Lymphatic  Hearts.—Many reptiles have small sac-
like organs lying just beneath  the skin in certain  portions  of
the  body, which,  from their containing  lymph and showing
                            Fig. 237.
                             i
      Pulmonary Artery.
 Heart of Crocodile, v, Veins, ao, Right
Auricle,  vt. Ventricles,  ap, Pulmonary
Arteries, a, A Vessel proceeding from the
Ventricle to the Aorta,  og, Left Auricle.
Pulmonary Vein.
  Right Auricle.
        Vena Cava.
Left Arch of the Aorta.
Right Aorta.
  Pulmonary Artery.

*« Pulmonary Vein.

~~ Left Auricle.
"a  Single Ventricle.
Ventral Aorta.
Heart of the Turtle.
pulsations,  are called Lymphatic Hearts.   In the  Frog,  two
such hearts are  situated on the back of the  animal, between
the joints of the thigh bones.
 418. What animals of this class have the most perfect form of a heart?  419 Whatkim.
of a portal system do we find among reptiles?  420 Describe lymphatic hearts. 
AND  PHYSIOLOGY.
237
f~
   421. Heart  of Fishes.—The heart consists of one auricle
and  one ventricle, which  are  covered  by a pericardium, and
the whole  organ is very small in proportion to the size of the
whole body, being from T \, th
to ToV„th its weight.   In the
osseous  fishes  the  heart  is
elongated  and  conical, while
in the Sharks and Rays it is
broader.   The  ventricle dis-
charges its blood through  the
aortic trunk  upon the  gills.
This  trunk  divides  up  into
a  large  number of  minute
branches  which  ramify upon
the gills,  and after the  blood
has received  its  oxygen from
the water, it is  collected by
a  corresponding  set of  ves-
sels, and emptied into another
trunk which  supplies all  the
rest of the body—which trunk
corresponds  to  the  aorta—
though  it  has  no muscular
power to propel  the  blood along.  After it has performed its
office  it  is collected by a system of vessels similar to veins,
and returned to the auricle.

   422. Pulsations  in  a   Minute.—Commonly not more than
twenty or thirty beats in  a minute may  be counted in  fishes,
while in  birds one  hundred  may be  counted  in  the  same
time.
   423. Portal Circulation.—In fishes, as in reptiles, there
seems to  be a double portal circulation.
 Circulation in Fishes,  a, Heart,  b,
Auricle,  c.  Ventricle.   d,  Circulation
through the Gills, or Lesser Circulation.
g,  Circulation  through the Body,  or
Greater Circulation,  e, Arteries, f, Veins.
 421. Why is the heart of the osseous fishes called a branchial heart?  What proportion
of the body does it constitute ?  Give the course of circulation.  422. What number oi
pulsations can be counted in the heart of fishes, and what number in birds ? 
238
Branchial Artery.
HITCHCOCK'S   ANATOMY

             Fig. 239.

                            Branchial Vesaels.
 Arterial Bulb.

Ventricle of the
    Heart.
 Auricle of the
    Heart.
 Venous Sinus.
Vena Portae,
 Liver, &c.
Intestine.
Vena Cava.
Dorsal Artery.
Kidney*.
Dorsal Artery, os-
    Aorta.
                   Circulating Apparatus of the Fish.
   424.  Accessory  Hearts —Caudal  Heart.—Among many
fishes are found what are termed  Accessory Hearts, or small
muscular organs which seem  to aid in the propulsion of blood
through the different parts of the body.  Thus, in the myxine,
the portal vein  is distended into a large  sac, which expands
and  contracts alternately;  and  in eels there  is found  upoa
424. What are the accessory hearts of fishes ? 
AND  PHYSIOLOGY.
239
both sides of the  last caudal vertebra a pulsating organ which
receives the blood  from  the delicate veins of the caudal fin,
and propels it  into the caudal vein, this  constituting  a true
caudal  heart.
   425. Fishes'  Blood.—The blood of
fishes, almost without exception,  is of a
red color, and contains oval and slightly
bi-convex  corpuscles.   In one family
they  are  distinguished  by  their  great
size, and thus resemble  those of frogs;
but other families have smaller ones.
                      Fig. 241.
                  Smaller  Circulation.
Fig. 240.
  Blood Corpuscles  of a.
Lamprey Eel; b, Skate.
Branchio-Cardia*
Canals.
Heart.
                   Greater Circulation.
             Diagram of the Circulation In Fishes.

   426.  Dorsal  Vessel, or  Heart of  Articulates.—In ar-
ticulata, a vessel or tube passes along the back of the body-
behind the intestines and in front of the chain of ganglia—
called the Dorsal Vessel, which  is divided into as many por-
tions as there are segments of the body.  This is really the
  What peculiarity in the tail of the eel ?  425. What is the color of fishes' blood, and
what are its corpsucles ?  426. What is the Dorsal Vessel of articulates ?
                             11 
240
HITCHCOCK'S  ANATOMY
  Circulatory Apparatus In the Lobster,  a, The Heart,  b, Ophthalmic Artery,  c, An-
tennar Artery,  d, Hepatic Artery,  e. Abdominal Artery.  / Sternal Artery,  g, Venous
Sinuses, h, Branchiae.


heart of the animal, since  by the contraction of its coats the

blood  or contained fluid  is forced along.   Small arteries are

given off from this dorsal  vessel  all  along  its  course.   This


                             Fig. 243.
 ^Circulation in Insects, a, Dorsal Vessel,  b, Principal Lateral Currents. The Arrow*
show the direction of the Fluid.

  plan, however, is seldom completely carried out, but is

  most fully exemplified in the class of insects which is
  partly  exhibited in Fig.  243. 
AND  PHYSIOLOGY.
241
      427.  Ventral  Trunk.—The blood which is driven forwards
    by this dorsal vessel is collected by a set of vessels which unite
    into a large tube called the Ventral vessel, or trunk, which
    returns it to the posterior part of the body.

      428.  Blood  of Articulates.—This fluid called blood is  a
    thin  liquid, yellowish brown,  red,  green,  or even colorless,
    rnd never containing corpuscles ;  and the  only reason why  it
    is  called  blood is,  that  it  circulates like the blood of the
    higher animals.

      429.  Chylaqueous  Fluid.—But besides this fluid there  is
    another  found in  the general or abdominal cavity  of the body,
    which, though not contained in orgms expressly designed for
    its circulation, yet  is  rapidly carried  though the body by
    means of the motion of the different segments of  the  animal,
    which in many of this order is incessant.   This fluid, unlike
    the true blood, is rich in corpuscles and easily coagulated,
    which gives it one of the essential characteristics of true blood
    in  the higher  animals.   It, however, must  probably be re-
    garded as  the  cylaqueous fluid of many  of the lower verte-
    brata.   Scorpions have arteries and veins.
      430.  Heart  and  Blood               Fig. 244.
    of  Crustacea.—Amongthe           jfl}
    crustaceans, such as the crab    J&    ^^
    and lobster, we find  a vessel    ^jr
    much shorter than the dorsal         $M&
    vessel of  most  articulata,    ^    *Sw
    which resembles a heart from    Blood Corpuscles of the Crab.
    ,   r.  ,  , i  , ..  .          i    Cells. B, Nucleated Cells.
    the fact  that it  is a  propel-
    ling organ and  has muscular fibers in its coats.   The blood in
    these animals is of a whitish or purple color,  and the  pulsa-
    tions of the heart vary in number from fifty-one to two hun-
    dred per minute.

    427. How is the blood returned that is circulated by the dorsal heart? 428. Describe
■*S  the blood of articulates.  429. What other fluid is found in these animals?  430. What is
    said of the heart and blood of the crab and lobster ?
 
_4_
HITCHCOCK'S  ANATOMY
   431.  Circulation  in Molluscs.—The  higher  orders of
molluscs show a  system of circulating vessels which seem to
be  arteries and veins,  with a  central  vessel answering  to  a
heart.   There  is usually  a ventricle  corresponding to  the
right ventricle in man, to send the  blood to the  respiratory
organ.   There  is also another cavity which corresponds some-

                           Fig.  245.
  Anatomy of the Snail, a, Mouth,  b, Foot,  d, Lung,  e. Stomach, f, Intestine, g,
Liver,  h, Heart,  i, Aorta. ,;, Gastric Artery.  I, Hepatic Artery,  k, Artery of the
Foot, m, Abdominal Cavity,  n, Canal conveying the Blood to the Lungs,  o, Vessel
carrying Blood from Lung to Heart.
what to an auricle,  which  receives the blood as it enters the
heart.   But with the exception of the vessels carrying blood
to the gills, there are  few  separate  tunes for  carrying this
fluid  through  the body, it being  left to  circulate  by imbi-
bition, or it is  effected  by means of the lacunar spaces, Fig
245.                                                F        S

  432.  Blood  of lllolluscs.—The blood of these animals ,
generally destitute of corpuscles,  and is sometimes  colorless,
though often white,  brown, red, or green.
  433. Contractions  of  the Heart—The  heart  does not
Wd% ^m *he *lrCuI,at0ry vessels in molluscs?  How is most of the fluid circu.
lated ?  432. What of the blood of molluscs ? 
AND PHYSIOLOGY.
243
expand  and  contract  regularly, but in a  spiral,  screw-like
manner,  like the peristaltic motion of the intestines.
  434.  Circulation  in the  Radiata  and  Protozoa.—In a
few polyps a vascular system is quite  obvious,  and may  be
inferred  in them all.  The blood is colcrless, and  has white
corpuscles.   In the Acalephse there  exists a circulating fluid,
which is thought by Agassiz  and Dana to be merely water,
intended to subserve the purposes of respiration rather than
nutrition.  The Echinoderms have  one heart, and sometimes
more.   The  Infusoria have pulsatory cavities, but  no  system
of circulation.
  433. How does  the heart pulsate?  434. What is the plan of circulation among tha
radiate animals ? 
CHAPTER   FIFTH.
PNEUMONOLOGY, OR HISTORY OF THE ORGANS OF BREATHING.
    —THE RESPIRATORY, VOCAL, AND CALORIFIC ORGANS.
         DEFINITIONS   AND   DESCRIPTIONS.

   435.  Location  of  Respiratory  Organs.—Sympathy   be-
tween the  Heart  and  Lunss.—Within  the  thorax  are  con-
tained  not only the central organs  of circulation, but other
organs closely related, and  connected with them, the Respira-
Vein of the Arm.
Right Lung.
Artery of the Arm.

Vein of the Arm.
Left Lung.
  Lungs, Heart, and Principal Vessels in  Man.  od. Eight Auricle, vd. Bight
 Ventricle, vg. Left Ventricle, a. Aorta,  ac. Carotid Arteries, vc. Vena Cava.
 t. Trachea,  vj, Jugular Veins.

 435. What organ-i^re contained in the thorax?  What is said of the sympathy be-
tween the respirat'»7*" and circulatory organs? 
            ANATOMY  AND   PHYSIOLOGY.         245

tory.   These are not only related by position, but are  mutu-
ally dependent on each other for their action. Thus, if severe
disease affect the  heart, the  lungs are very apt by imperfectly
or  irregularly performing  their  offices,  to  show  their sym-
pathy.    In  like  manner,   if  the  lungs  exhibit  disease,
sooner  or later the  heart  is  sure to  manifest  its  sympathy
with its suffering neighbors.
  436   The  Lungs,   their Shape, their  Color,  Lobes  c_
the Right  Lung, Capacity of  the Right  Lung, Amount of
                             Fig. 247.
  A View of the Bronchia and Blood-Vessels of the Lungs as shown by Dissec-
tion, as well as the relative Position of the Lungs to the Ileart.  1, End of the
Left Auricle of the Heart.  2, The Right Auricle. 3, The Left Ventricle with its
Vessels.  4, The Right Vertricle with its Vessels.  5, Pulmonary Artery. 6, Arch
of the Aorta.  7, Superior Vena Cava.  8, Arteria Innominata.  9, Left Primi-
tive Carotid Artery.  10, Left Sub-Clavian Artery.  11, The Trachea.  12, The
Larynx.  13, Upper Lobe of the Right Lung.  14, Upper Lobe of the Left Lnng.
15, Trunk of the Right Pulmonary Artery. 16, Lower Lobes of the Lungs. The
Distribution of the Bronchia and of the Arteries and Veins, as well as some of
the Air-Ceils of the Lungs, are also shown in this dissection. 
246             HITCHCOCK'S   ANATOMY

Blood  in  each  Lung.— The essential  organs  of respiration
are the  Lungs.    These  are light  solids, two in number, and
occupy nearly four fifths  of  the  cavity  of the  chest.    They

                                 Fig. 248.
  An Anterior View of the Thoracic Viscera in Situ, as shown by the Removal of their
Anterior Parietes.  1,  Superior Lobe of the Eight Lung.  2, Its Middle Lobe.  3, Its
Inferior Lobe. 4, 4, Lobular Fissures.  5, 5, Internal Layer of the Costal Pleura form-
ing the Eight Side of the Anterior Mediastinum.  6, 6, The  Eight Diaphragmatic Por-
tion of the Pleura Costalis.  7, 7, The Eight Pleura Costalis on the  Eibs.  8, Superior
Lobe on the Left Lung.  9,  Its  Inferior Lobe.  10, 10, Interlobular  Fissures.  11, The
Portion of the Pleura  Costalis which forms the Left Side of  the Anterior Mediastinum.
12, The Left Diaphragmatic  Portion of tho Pleura Costalis.  13, Left Pleura Costalis.
14,14, The Middle Space between the  Pleurae, known  as tho Anterior Mediastinum.
15, The Pericardium.  16, Fibrous Partition  over which the Pleurae are reflected.  17
The Trachea.  18, Thyroid Gland.  19, Anterior Portion of  the Thyroid Cartilage.  20,
Primitive Carotid  Artery.  21,  Subclavian Vein.  22, Internal Jugular Vein. 23, Bra>
chio-Cephalic Vein. 24,  Abdominal Aorta. 25, Xiphoid Cartilage.
436. What are the Lungs? 
AND   PHYSIOLOGY.
247
are of a conical shape, the  apex  pointing upwards, the base
resting on the Diaphragm, of a pinkish gray color, frequently
dotted with black  spots,  and divided  by a  deep  fissure into
two  lobes.   The right  lung  is shorter  in its  long  diameter
than the left, on account of the liver  which raises  the right
side  of the diaphragm higher than the left.   The right lung
is subdivided again, so that it is really made up of three lobes
instead of  two.   It has also a larger capacity than the left,
since the position  of the  heart,  considerably  upon the  left
side  of the  median line  of the body, occupies a portion of the
left thorax.   Each of the lungs ordinarily contains a pint of
blood.
  437. Lobules  of the  Lungs.—A closer  examination  of the
lungs shows them to be  made up of small bodies called Lung-
lets. These are from ¥Vth to -r'ath  of an inch in diameter, and
of a  conical or pyramidal shape.  They are much more clearly
defined  in  small children than in adults.   Fig.  249,  by the
  A Lunglet with a Section of a Bronchial Tube, a, Bronchus, b and c, Vessels •/
B'-onchial Lining Membrane,   d,  d, e, e, Spaces between contiguous Lobules, contain-
ing the Terminal Pulmonary Arteries and Veins supplying the Capillary Plexus (f, f,)
tu the Meshes of which the air gains access by the Lobular Passages.
  Give their shape, color and division.  What are the lobes of tho lungs? Which is tha
largest lung, and why the difference ?  437. How are the lungs made up? At what pe-
riod of life can the lunglets be best seen ? 
248
HITCHCOCK'S  AXATOMY
hexagonal  figure  surrounding the bronchial  tube,  shows  a
section of a lunglet, or lobule of the lung.
  438.  The  Pleura—Pleurisy—Root of  the  Lungs.—The
lungs are immediately invested with a serous membrane called
the Pleura, which is also the inner lining  membrane of the
walls  of the chest:  so that when the lungs are fully inflated,
these two surfaces are brought in contact, and in  the act of
respiration move slightly  upon each other.   And if any por-
tion of these membranes becomes inflamed, the disease results
which is known as Pleurisy.  In the acute  or early stage of
this disease, if a long breath be drawn, intense pain is felt at
the lower portion of the lung.   This is owing to the friction
of these  inflamed  membranes  one upon  the  other,  and the
reason why the pain is severest in the lower part of the lung,
is that this part of the lung moves over the largest space in
breathing.   The  vessels for supplying blood,  emptying it
and nourishing the lungs,  as well as  the air-vessels, nerves
and  lymphatics, are all collected  together in one bundle at
the inner side of these organs,  and are collectively called the
Root of the Lungs.
  439.  T!je Air Passages.—The vessels which are especially
designed for the purpose  of conveying  air into the lungs are
the Larynx, from the Greek meaning   a whistle, since sound
is made in it—the Trachea, meaning  rough, as is its struc-
ture—the  Bronchia, meaning the windpipe, (Fig.  250,  p.
249), and  the intercellular  passage.3 which terminate in the
air-cells.   (Fig. 252, p. 250.)
  440.  The Larynx.—The Larynx is  a conical cartilaginous
tube from one to two inches in diameter, opening upwards into
the Pharynx, and terminating below  in the Trachea.   (See
Organs  of Voice.)
  441.  The Trachea.—The Trachea is a  cartilaginous tube

 438. What are the lungs covered with, and what is the chest lined with? What is
Pleurisy?  What is meant by the root of the lung?  439. Give the names of the dif-
ferent parts of the air-passages. 440. Describe the Larynx. 
AND  PHYSIOLOGY.                 249

          Fig.  230.
  The Larynx, Trachea, and Bronchia, deprived of their Fibrous Covering, and with the
 outline of tho Lungs.  1, 1, Outline of the Upper Lobes of the Lungs.  2, Outline of the
 the Middle Lobe of the Eight Lung. 3, 3, Outline of the Inferior Lobes of both Lungs.
 4, Outline of the Ninth Dorsal Vertebra, showing its relation to the Lungs and the Ver-
 tebral Column.   5, Thyroid  Cartilage.   6,  Cricoid  Cartilage.  7, Trachea.   8, Eight
 Bronchus.  9, Left Bronchus.  10, Crico-Thyroid Ligament.  11, 12, Eings of the Tra-
 chea.  13, First  Eing of the Trachea.  14, Last  Eing of  the Trachea, which is Corset-
 shaped.  15,16, A complete Bronchial Cartilaginous Eing. 17, One which is Bifurcated.
 18, Double Bifurcated Bronchial Eings.  19,  19,  Smaller Bronchial Kings.   20, Depres-
sions for  the Course of the large Blood-Vessels.


 about one inch in diameter, made  up of from fifteen to twenty

cartilaginous  rings,  commencing  at  a  point  nearly  opposite

the fifth cervical vertebra, and extending as low as the second

dorsal, or top of the sternum,  where it divides into two bron-

chi extending  to each lung.    These segments of the  trachea

are not perfect rings, since they  complete only about five sixths

 441. now is the trachea made up ?  Where does it divide into the two bronchi ?  Ar»
the segments of  the trachea perfect rings ? 
250
HITCHCOCK'S   ANATOMY
FIG. 251.
                     Capillaries of the Human Lung.
of a circle,  the remaining sixth consisting of smooth or invol-
untary muscular fiber.
   442.   The  Bronchi.—Intercellular  Passages. — Citca 1
Air-Cells.   Their Number.—As soon as  the Bronchi fairly
                              Fig. 252.
  A Magnified View of a Section of the Lung, showing the Arrangement of some or
the Lobules, the Communication of the Air-Cells in one Lobule and their Separation
from those of the adjoining Lobule.  The Eamifications of the Blood-Vessels in the
Texture of the  Lung  and their Course through the Air-Cells are also seen. 1, 1,
Branohes of the Pulmonary Veins.  2, 2. Branches of the Pulmonary Artery. 
AND  PHYSIOLOGY.
251
enter the lungs, they immediately divide and subdivide, until
they  have diminished to a diameter about  one fiftieth  of an
inch,  and some of them are within one eighth of an  inch of
the outside of the lung.   After this they are changed in their
structure,  and become channels hollowed  out in the cellular
tissue of  the  lung, and  are called Intercellular  Passages.
These terminate in minute
cells, called  Csecal Air-Cells.
These cells have an average
diameter of Ts uth of an inch,
and accumulate around  each
terminal bronchus to the num-
ber of 17,790, making a total
in the lungs of 600,000,000,
which, if  spread out,  would
make an area of  cell surface
of  132  square feet;  Dalton
says  1,400 square feet.

   443.  Composition  of the
Air-Tubes.    Their  Mucous
and   Pleural   Surfaces.—
These air-tubes just described
are  essentially composed  of
cartilage and  fibro-cartilage,
and  lined  throughout  with
mucous  membrane.    Hence
we see  that this membrane,
though  situated  nearest the
center of the body,  lines the
ontside  of  the lungs,  while
the Pleura, although nearer
the surface of the body, lines
 Longitudinal Section of the Tc-mina
tion of a Bronchus. 1, Bronchus. 2, Ct_
cal Air-Cell.  3, Orifice of the same.

           FIG. 254.
Bronchial Tube laid open.
 442. What are the bronchial tubes subdivided into? IIow large are the cecal air-cellsi
IIow many around each terminal bronchus?  What is their aggregate number? Whai
Is the area of cell surface in the lungs?  443. What is the composition of the air-tubes
Which is really the inside and which the outside of the lungs? 
252
HITCHCOCK'S  ANATOMY
the  interior of the  lungs.   This apparent  contradiction of
terms arises from considering that portion of the body as ex-
ternal which is in contact with the air, in the same manner as
the intestines ; the anatomically external surface being phys-
iologically the internal surface.
   444. The Substance of the Lungs.—The substance of the
lungs is entirely made up of arteries, veins, lymphatics, and
bronchial tubes, connected by areolar tissue.  And when in-
flammation takes place in this substance, the disease is known
as pneumonia, or lung fever.
   445. The  Essential Muscle of Respiration—Process of
Breathing—The Rest Gained by the  Respiratory Muscles
—The  muscle which  performs  the most essential  part of
breathing is the diaphragm.   This by its contraction produces
inspiration, but does not directly produce expiration.   Breath-
ing is performed as  follows.   The cavity of the chest is va-
riable  in  size; made  so by the movement of the diaphragm
upwards and downwards.   For as the sides and upper portion
of the chest are unyielding  walls,  if the  diaphragm be de-
pressed the cavity of the chest is enlarged, a partial  vacuum
is  produced, and the air  rushes in to  supply  the vacancy.
This is inspiration, and is purely an active  muscular effort.
Expiration,  however, is quite the reverse, being wholly a pas-
sive exercise.   For when the  lungs are filled, the contents of
the abdomen are depressed by the descending diaphragm and
the ribs  are  elevated, both of which parts offer  resistance to
the inhaling force.   Consequently, when the diaphragm and
the other respiratory muscles are relaxed, several muscles of
the back,  abdomen, and chest, by their  elastic tonicity, force
air again out of the  mouth, which completes the process of
expiration without expending any nervous energy, and at the
same time gives rest  to the muscles employed in breathing.
Hence the muscles of respiration  are not  all the time in ac-

 444. What is the substance of the lung composed of ?  Define pneumonia.  445. What
is tho principal muscle of respiration? Describe the mechanism of breathing. Which
act is active and which Is passive ? When do the respiratory muscles rest? 
                 AND  PHYSIOLOGY.              253

tion, but as the period occupied by expiration  is longer than
that of inspiration, consequently  they rest  during a longer
time than they are in action.
          FUNCTIONS  OF  THE  LUNGS.

  446.  The  First   Object  of  Breathing.—The  immediate
object of breathing  is to bring air into  the  lungs and carry
it out again after it has performed its office';  and the function
of the lungs is to expose as large a surface of blood as possible
to the air inhaled.   The ultimate objects of this arrangement
are to remove waste products  from the  body, which exist in
the form of carbonic acid and water, and also to generate the
animal heat necessary.   A third, but by no means an  incon-
siderable value of this  function, is to convert  the gluten of
vegetable food into  fibrin.
  447.  Another  Use of  Breathing,  Purifying the  Blood
— Endosmose and  Exosmose.—The impurities of the blood
—carbonic acid and water—are exchanged for the oxygen of
the atmosphere.  This is not effected  by actual contact of
blood and air,  but through  an intervening membrane, the
wall of  the  air-cells.  It is  a remarkable property of mem-
branes,  both animal  and vegetable, called  Imbibition, or  En-
dosmose and  Exosmose, that  allows  fluids and  gases to pass
through them  in   opposite  directions at  the  same  time.
Through the membrane of the lungs, the carbonic acid, which
has more affinity with pure air than for  the blood, passes out-
wards, while the pure air, containing oxygen, has  an affinity
for  the  blood, and passes inwards.
  448.  Amount  of  Air Used in Breathing—Causes of i V
Variation—Capacity of the  Chest.—The  average  amount
of air which passes  in and out of the lungs at each inspiration

  446. What is the object of breathing, and what is the  function of the lungs ?  What
Siree processes are accomplished by this process? 44T. How does breathing purify tho
>lood? Describe the process of imbibition. 
254
HITCHCOCK'S  ANATOMY
and expiration is about twenty cubic inches, and the  amount
passed through them in twenty-four  hours  about  360  cubic
feet, or, as  others  estimate it, from 3,000  to 5,000  gallons
every day.  This varies greatly.   In' the first place, the  lower
the temperature the greater the  amount of  animal  heat to be
generated, and consequently the  greater the quantity of air
to be  consumed.   Also a  person laboring in the open air
breathes more deeply than one confined to the house.   Again,
the capacity of the lungs modifies the quantity of air inhaled.
And this  capacity depends more  upon the height of the indi-
vidual than any other  physical  feature.   From a series  of
5,000  observations made by Dr. Hutchinson,  the following
principle  is deduced.    " For  every  inch   of  stature  from
five to six feet, eight additional cubic inches of air are  given
out at  a forced expiration after a full inspiration."   That  is,
if a person  five feet  and six inches in height can  expire 422
cubic  inches,  a person  five feet  and  seven  inches  can expire
430 cubic inches.
   449. Effect  of Corpulence   on  Capacity  of   Lungs —
Another fact of importance  is deduced  by  the  same  experi-
menter—that if a  person  exceed  the  average weight on ac-
count of corpulence, the capacity of the lungs  decreases in a
marked ratio,  as is stated  in  these words :  "' When the man
exceeds the  average weight (at each height) by 7 per cent, the
vital capacity decreases one cubic inch per pound for the next
thirty-five pounds above that weight."
   450. Function  of the  Red  Corpuscles— The   red  cor-
puscles of the blood seem to be the carriers of oxygen  from
the lungs to the various parts of  the body.  The  prominent
reason for this belief is that the serum  and  salts of the blood
have but a very slight  power of absorbing  oxygen, while the
discs condense this gas at once.
  448. How much air is used in each act of inspiration, and how much each day?  How
does temperature and exposure to the open air affect the amount respired ?  Upon what
does the capacity of the lungs depend ?  Give the law and its  example.  449. IIow does^
corpulence affect the capacity of the chest? Give the formula. 450. What  is the prob-
able function of the red corpuscles of the blood ? 
AND  PHYSIOLOGY.
25-
  451.  Inspirations  compared  with  Pulsations —Quan-
tity  of  Watery  Vapor Given  off  in  Twenty-four  Hours-
Amount of  Carbonie  Acid  Exhaled—The  Amount  of Solid
Carbon given  off.—If we compare the number of inspira-
tions in a minute with the pulsations of the heart, we shall
find  the proportion of the former  to the latter is as one to
four or  five in the human adult.   Every fifth breath is usually
deeper  than the preceding four,  and  the time  occupied by
each respiratory act is about  three  and a half seconds;  and
all the  blood in  the body (when in vigorous exercise) probably
is exposed to the air in the lungs every  two minutes.
   The  quantity of watery  vapor which is  ordinarily exhaled
from the lungs  in twenty-four hours ranges from sixteen to
twenty ounces.   The  amount of carbonic acid, however, varies
much more, being from one to three pounds in  twenty-four
hours,  and the  causes of  variation are temperature, age,  sex,
state of health or disease, development of the body, muscular
exertion or repose, sleep or watchfulness, and period  of the
day.   " This gas (carbonic acid) contains in every 100 pounds
28  pounds of  carbon (charcoal)  and  72  pounds of oxygen
 (gas).    Hence the weight of carbon  which  escapes in  this
form from  the lungs of a full-grown man  varies from five  to
 fifteen  ounces in twenty-four hours."
   452. Respiration  as  a  Source  of  Aniniaf  Heat.—The
 value of the  function of breathing as a means  of  producing
 animal heat,  will be  considered  under  the organs for produc-
 ing heat.
   453.  Changes in  the Food  effected  by  Respiration.—
 A third object of breathing is to effect such  changes in the
 food that it can be directly converted into the  different tissues
 of  the body.   Hence the oxygen of the air is a part of the
 food that we live upon.   For although the gluten which is so
  "^"matl7t_-TolatlTe number of inspirations and pulsations of the heart? What
 length of time is occupied in breathing?  What quantity of vapor of water is, exhaled in
 twenty-four hours, and what amount of carbonic acid? IIow is this amount modified
 What weight of carbon or charcoal is given out of the body by the lungs every day?
  453. What effect has the oxygen of the air upon the glutinous portion of our food ? 
256
HITCHCOCK'S  ANATOMY
largely contained in vegetable  food  very closely resembles
fibrin (which is the form that the nutrient portion of the food
must be in before it can nourish  the greater part of the  body,
and especially the muscles), still chemical analysis shows that
the gluten must receive another equivalent of oxygen before
it is fitted to reproduce the different tissues of the body.   And
the only way in which  this oxygen can be given to  the body
is either through the lungs or skin.
  454. Amount  of   Air which the  Lungs can Contain —
The amount of air which the lungs actually do contain is by
no means the amount that should be actually supplied to them.
For the air which surrounds the body is very rarely indeed
perfectly pure, but is  contaminated with  the  previously ex-
haled  breath,  on account of the law of diffusion of gases,
which  is, that when  two gases are  brought  into contact they
immediately commingle with each other.   Experiment  shows
that between 350 and 400 cubic feet of air  are actually ex-
haled  during  the twen'y-four  hours ; but experience  shows
that the least quantity  which should be allowed for  dwelling-
houses, shops, and school-houses, should be 800  feet in order
to furnish a sufficient supply of oxygen.
               CALORIFIC  ORGANS.

  455.  Heat-producing  Organs—Theory of  Animal Heat.
—The organs which produce animal heat are essentially those
employed in the act of breathing and the circulation of the
blood,  and consequently already  explained, but  the actual
m thod by which it is produced has for a long time perplexed
physiologists.   The theory which now is most readily accepted
makes the function to be a  chemico-vital one, or a  chemical

  What is that element which principally nourishes the muscles ?  454. What is the law
of diffusion of gases, and what modifying influence does this have on the hygiene of res-
piration ?  How many cubic feet of air should be allowed to every in-door laborer or
student? 455. What are  the heat-producing organs?  What is at present the most
readily accepted theory of animal heat? 
AND  PHYSIOLOGY.
257
change (oxydization) dependent  upon  vital  energy,  being
nearly analogous to the burning of a  candle  or the combus-
tion of wood and coal in the stove.
  456. Process of Producing  Animal Heat.—As  the  oxy-
gen in the inspired air enters the lungs  and is brought  into
contact with the blood  through  the wall of the air-cells, the
carbon of the venous  blood unites with it, forming  carbonic
acid, and  heat is generated.   This is precisely the same thing
that takes place in the furnace, where the air  enters  through
the draft  supplying the oxygen, and the coal  furnishes the
carbon, the result of the union being heat.   But it is not in
the lungs  alone that this heat  is generated :  for we  have al-
ready seen that the blood is highly charged with oxygen as  it
passes through the arteries to the various organs of the body.
And as it passes through the capillaries in every part of the
system, it there  receives  an equivalent of carbon, the waste
of  the  system producing carbonic acid, in  which operation
heat is given off.   Hence we see that  heat  is  generated not
only in the lungs  but in every part of the  body, and that  it
is incessantly being produced,  which is a reason why the ex-
tremities of the body are constantly kept at their proper tem-
perature ; for if all the heat were to be generated in the lungs,
very frequently the blood would become chilled in its passage
to the extreme capillaries.   We also  see that forced  respira-
tion has the  same  effect as increasing the  draft  of air into
the furnace, and that the fuel of the human  system is  sup-
plied by means of the food placed in the stomach.
  457.  Temperature  of Human Body.—The temperature of
the human system is 98° F., and this it is invariably found to
be in all climates  and seasons when the individual is in pos-
session of perfect  health.   So that in most climates  the tem-
perature of the body is  above that  of the surrounding atmos-
 456. Describe the process. Is all the heat of the body generated in the lungs?  Where
In the body is it not generated ? What is the fuel of the body?  Where is the draft?
457. What is the temperature of the human body?  How is the heat of the body com-
pared with that of nearly all climates ? 
258
HITCHCOCK'S  ANATOMY
phere, and we are constantly giving off heat to  the air which
envelops us.

  458.  Manner  in  which  the Body is maintained at  its
uniform Temperature.—The manner in which  the  body  is
kept at the uniform temperature of 98°,  is a subject  of deep
interest.  It is partly accomplished  by radiation, since the
body  is  ordinarily warmer  than the  air about  it, and also
partly by inhaling the cool air  into the air passages.   It is a
well-known principle  in chemistry, that, when any substance
passes from a  more solid  to a  less solid  condition,  as  from
solid to liquid,  or liquid to a gas, heat is absorbed, or,  in more
common language, cold is  made sensible.   This is seen in the
application of  water,  alcohol, or ether, to the skin,  when a
sensation of cold is felt, which  is owing to the fact  that the
substance applied is  passing from  the  form  of a liquid  to
that of a vapor.   Now the same thing takes place when the
perspiration is  allowed to  evaporate from the  surface of the
body.   The increased flow of blood, as brought about by the
exercise,  or  the  high temperature of  the surrounding  at-
mosphere, stimulates the vessels of the skin to more energetic
action, and  sensible perspiration is poured out upon  the sur-
face of the body.  This, however, is now in contact  with  the
currents of air always present about the body, and it is readily
thrown out into a state of vapor, and  in accordance  with  the
chemical principle just stated, heat is absorbed from the body
producing its uniform temperature.

   458a.   It  should  be mentioned here,  that of late many
experiments  have been carried on which  seem to  show us
that  the above-mentioned theory of animal heat can not be
fully  adopted.   For  it is well known  that  many  chemical
combinations besides  those of mere oxydation or "burning''
produce heat;  and  many of these  processes  are  constantly
taking place in the body.  But  all  the  facts  hitherto  ad-

  458. How is the body kept at its uniform temperature?  What chemical principle
Illustrates this view ? 458a. Give the result of recent experiments. 
                  A X 1)   PHYSIOLOGY.              259

vanced do not by any means entirely overthrow the old  theo-
ry.   They  show  us that the theory of combustion does not
cover the  whole  ground, but that  other  causes, as well  as
oxvdation produce animal heat.   And  we propose the idea
that animal heat, like digestion, is  a chemico-vital process,
that is, a process under  the immediate influence of chemical
changes, but entirely under the control of  the vital princip'%1
since animal heat can not be maintained after death.
   ORGANS   OF  THE  VOICE.

DEFINITIONS  AND  DESCRIPTIONS.
  459.   The   Larynx;   its
Cartilages.—The Larynx in
all animals is the essential or-
gan  for the production of the
voice.  It has  also very much
the same structure  in every
animal which has the power of
expressing its feelings by the
voice.   A cartilaginous tube,
imperfectly conical, the base
directed upwards,   made  up
of distinct  portions or seg-
ments slightly movable upon
one another, and vvitli a  cer-
tain  portion  of the  channel
lengthened into a narrow and
elongated opening, constitutes
a larynx.  In  man this organ
is made  up of seven distinct
portions  or  cartilages,  two
Arytenoid  (pitcher-shaped),
Fig. 255.
 A Lateral View of the Larynx.  1, Os
Hyoides.  2,  Thyreo-Hyoid  Ligaments.
3, Cornu Majus of the Thyroid Cartilage,
4, Its Angle and  Side. 5, Cornu Minus
C, Lateral Portion of the Cricoid Carti
lage. 7, Rings of the Trachea. 
260           HITCHCOCK'S  A N A T O M Y

two  Cuneiform (wedge-shaped), one  Cricoid (ring-like), one
Thyroid (shield-like,) and one Epiglottis ;cover to the Glottis).
These together  form the small  prominent portion of the neck
known as Adam's apple.
   460.  Thyroid  Cartilage.—Arytenoid  Cartilages—Cu-
neiform  Cartilages.—Cricoid  Cartilage.—Vocal  Cords.—
Ventricle of the  Larynx.—Muscles  of  the  Larynx.—The
Thyroid Cartilage is so arranged as to form a framework for
the movable portions of  the organs of the voice, and this is
the principal  cartilage that forms the Adam's apple.   The
Arytenoid Cartilages can be moved  by the  small  muscles of

            Fig. 25G.                       Fig. 257.
 A Front View of the Thyroid Carti-    4, Its External Angle.  5, Its Internal
[age.  1, Left Half of the Cartilage.  2,    Angle.
Anterior projecting Angle.  3, Superior
Margin. 4, Its Notch. 5, Inferior Margin.
6, 6, Cornua Majora.  7, 7, Cornua Minora.
the  larynx.   The  object  of this  movement is to  relax or
tighten the vocal cords, so that the different pitch and quality
of voice may be perfected.   The Cuneiform  Cartilages are
about half an inch in length, and enlarged  at each extremity.
These  are  sometimes wanting.   The  Cricoid Cartilage is of a
ring-like appearance, and  resting directly upon  the  rings of
 -------------------------------------r----.
 459. What is the essential organ of voice in all animals?  Give the anatomy of the
larynx.  Name the seven cartilages.  450. Describe the thyroid and arytenoid cartilages.
Describe the cuneiform and erieoid cartilages. 
AND   PHYSIOLOGY
201
the trachea, being of a  little longer diameter  than the trachea
The Epiglottis is the most movable of all the vocal cartilages.
Fig. 258.
Fig.  259.
  A Lateral View of the Epiglottis Carti-
lage. 1, Anterior or Convex Surface.  2,
Posterior or Concave Surface.  3, Superior
Margin.  4,  Inferior  Margin  or Pedicle.
5, Its Sides.  The Openings of the Muci-
parous Ducts are also shown.
FiG.  260.
2    3
  A. Front View of the .ricoid Cartilage.
i IlS Internal Face.  2, The Cavity  of
In*  Larynx as formed by this Cartilage.
8, Its Inferior Surface. 4, The little Head
or Convexity for Articulating with the
Arytenoids.   5, The Surface cf the Su-
perior Edge for the Attachment o/ tho
Lateral Crico-Arytenoid Muscles.
It  in shape resembles a cord-
ate or  heart-shaped leaf, at-
tached by  its apex to the up-
per edge  of the glottis, and
has a  wide range  of motion,
 in  order  to completely close
 up the passage into the lungs,
 or leave  a free communica-
 tion between  them  and  the
 air.   It  also aids  in deaden-
 ing sounds, as it is  suddenly
 brought down  upon  the glot-
 tis.  All  these  cartilages very
  A Posterior View of the Articulations of the Cartilages of the Larynx.  1, P°«
Face of the Epiglottis.  2, Appendices of the Os Hyoides.  3  Its Cornua   4, Latera
Thyreo-Hyoid  Ligaments. 5, rostertor  Face of the Thyroid Cartilage^ 6,  Arytenoid
Cartilages7 7, Cricoid CarMlrgr-  8, Cricc-Arytenoid ArMculation.  9  *«£»"££;
Thvroid Li-ament.  10, Cornu Minu» of the Thyroid Cartilage.  11  A»tenor Cnco-
Thyroid Ligament.  12,'Ligamentous Portion «f the fir* King of th. Trach.a.
 
262
II I T C II COCK'S   A \ A T O M Y
frequently  become  considerably  ossified   in   males  in  ad-
vanced age.
   The Vocal  Cords or ligaments are folds of white fibrous tis-
sue, covered  by mucous membrane, and are made to vibrate
when the air is forced over them.   Hence ulceration, or  any
Fig. 2C1.
Fig. 262.
  A View of the Larynx from above,
showing the Thyreo-Arytenoid or Vocal
Ligaments.  1, Superior Edge of the La-
rynx.  2, Its Anterior Fiice.  3, Cornua
Majores of the Thyroid Carthage. 4. Pos-
terior Face of the Cricoid Cartilage.  5, 5,
Arytenoid Cartilages.  6, 6, Thyreo-Ary-
tenoid Ligaments. 7, Their Origin within
the Angle o  the Thyroid Cartilage.  8,
Their Terminations at  the Base of the
Arytenoid Cartilages.  9, The Glottis. 10,
Anterior Part of the  Inferior Surface  of
the Cricoid Cartilage.
  Muscles of Human Larynx.  G. E. It.
Thyroid Cartilage,  r. w. A', to. Cricoid.
N. F. Arytenoid.  T. V. Vocal Ligaments.
iV, X. V. K. f. and N. I. .Muscles Of La-
rynx.
alteration in the structure of these cords, will produce hoarse-
ness, a  loss  of intonation—a whispering—or some change in
the quality  of the voice.   The cords just  mentioned are not,
however, the only ones that  exist in the larynx, for  these ar.
the upper ones, while another pair called  the  inferior  cords,
exist below  the others,  leaving a cavity known as the ventricle
of the larynx, (Fig.  263,  p. 263),  which  seems  essential to
the  proper  production of  sound : although  there is nothing
analogous to  it  in the ordinary  musical  instruments.   The
muscles connected  with  the larynx are eight: five of  them
 What is the epiglottis?  Of what are the vocal cords composed?  What is the ven-
tricle of the larynx ?  How many muscles belong to the larynx ? 
AND   PHYSIOLOGY.                25?

         Fig. 263.
   Cartilages >* Larynx and Epiglottis, a. Arytenoid. 6. Its Superior Cornu.  c. I»
  ffioi Cornu.  d. Cricoid. /. Perforation of Epiglottis,  i. Upper Part of Thyroid.
  t. Traohea. h. Tubercle.
pas_ between tho different cartilages, and are of use  in  regu-
lating the size of the  glottis and the tension of the vocal cords,
while the three  remaining  go  from the epiglottis to the dif-
ferent  parts of  the  larynx, solely for  the purpose of moving
this  valve to aid in articulation and closure of this passage to
the lungs.
   Which move the cartilages, and which are distributed mainly to the epiglottis ?
                                 12 
264
HITCHCOCK'S   ANATOMY
         FUNCTIONS  OF  THE  LARYNX.

  461.  Similarity of the Larynx to  a  Reed Instrument.—
The larynx, as  an organ  of sound, very much resembles a
reed instrument,  or  the reed  pipes  in  an organ.  For we
have the reed, or rather the reeds, in the vocal cords, and the
column  of  air in  the  pharynx and mouth.  This, however,
differs from the proper reed instrument  by the vibration of
free edges of the reed,  and also by the power of tightening or
relaxing the cords to produce different pitches of tone ; for in
the hautboy,  bassoon, and similar  instruments,  the  tone is
regulated by the length of the  vibrating  column of air, which
is controlled by  the keys and finger-holes.
  462.  Use of  the Cartilages.—The  arrangement of  the
cartilages of the larynx is such as to give form and  stability
to the organ, and  at the same time a firm attachment  to the
vocal cords, muscles,  and ligaments.   In  male adults these
are much larger than in females, since the voice of the former
is heavier and of a much lower  tone than that  of the latter,
requiring  greater length  of vocal cord,  and   consequently
firmer points of attachment.
  463.  Organs Essential  for  tnc  Production of  mere
Sound.—The vocal cords, together  with the diaphragm, ab-
dominal muscles,  and lungs,  are all the  organs which are
necessary for  the  production of sound.   But  the quality of
sound and articulation are produced and modified very essen-
tially by other parts of the body.
  464.  Use of  the Cavity  in  the Frontal Bone—The si--
nus, or cavity in  the  frontal bone which communicates with
the pharynx, is a  very important  member of the vocal organs,
as it imparts resonance to the voice in the same manner as the

  461. What kind of instrument does the larynx resemble? What correspond to the
reeds? 462. Of what use are the cartilages?  Are the vocal cords longest in man or
woman ?  What is the result ofit ?  463. What organs of the body are necessary for th«
production o f sound ?  464 Of what u;e is the cavity in the frontal bone ? 
AND  PHYSIOLOGY.
205
hollow portion of the violin and violincello, or the long tube of
brass instruments, gives the proper tone to these instruments.
The want of such  a  cavity for the perfection  of  the  human
voice is well appreciated, when  a person is suffering with a
severe cold  in  the  head,  as  it  is termed.   In this  case the
voice is of an extremely nasal character, because the passage
to the frontal sinus is closed up by a thickening of the lining
membrane, which prevents a resonance of the tones made in
tae larynx.
   465.  Function of  the  Nostrils in the  Voice.—An open
passage  through the  nostrils  is  also very important for the
production of perfect  tones of the voice.   For when this is ob-
structed in any  way, the head or nasal tone is invariably pro-
duced.
   466.  Function  of the  Tongue in  the  Making of  Ar-
ticulate  Sound—Not Absolutely Essential.—The tongue
is  the  chief organ   of articulation,  and in  connection with
the  lips and teeth, the tones made  in the glottis are  either
lengthened or shortened, and otherwise modified  to form the
different letters.  If  either of these organs is deficient in sub-
stance or function, the  articulate sounds are  imperfect;  as,
for instance, the letters T,  D, L, F, and  S,  which require a
full development of all the parts for their  perfect enunciation.
It  is, however,  stated as a fact, that  some people  have been
known to articulate words with distinctness after  the tongue
was removed by a gun-shot wound.

             HYGIENIC  INFERENCES.

   467.—1.  From the size of the lungs we see that they are
organs of great importance in the system.
   4(38.-2.  Liability of the  Lungs to Disease.—On  ac-
count of their delicate  structure  and constant use, they are
  What produces the talking through the nose, as it is termed?  405. IIow do the nos-
trils affect the voice ?  466. What use has the tongue in speech ? Also the teeth and
lips? Is the tongue always absolutely essential ? 467. What does the great size ©f tho
lungs show us ? 
'_<>6            HITCHCOCK'S   A N A T O M V

liable to disease, and consequently need especial care to keep
them in health.
   469.—3.  Action  of   the  Lungs  Essential  for  their
Health.—One important item to  secure  the  health of these
organs,  is to keep every part of them in action.   Hence pres-
sure of  clothing, or any thing else that prevents the complete
filling of the lungs by breathing,  is quite sure to  induce  dis-
ease.   For if but a very few of the millions of air-cells con-
tained in the lungs are allowed to lie inactive or  useless, na-
ture will attempt their removal by means  of the  lymphatics,
and this removal is often  the  commencement of fatal  disease.
Therefore it is a good  practice for every one, and especially
sedentary persons,  several times each  day to throw back  and
downwards the shoulders, and  slowly  fill  the lungs  to their
utmost capacity, and then permit the air to escape slowly, be-
cause in this way every cell in the lungs will be used.
   470.—4.  Pure   Air  is  Essential  to   Healthy  Lungs—
Life  Depends  on  Breathing   Pure  Air.*—All mechanical
and chemical impurities of the  air inhaled induce and  ag-
gravate  disease.   Indeed, the  most important hygienic  rule
for the lungs is to breathe pure air.   Mechanical impurities,
such as dust and vapors, are eminently injurious,  but  not so
much so as  the chemical impurity, carbonic acid, which comes
from the exhalations of men and animals,  and  the  burning of
  * Black  IIolk op Calcutta.—One of the most awful instances of suffocation on rec-
ord, is connected with what is known as the Black Hole of Calcutta.  When Calcutta
was taken by the Indian forces, the British garrison, numbering 146 men, were confined
as prisoners of war in the dungeon of the fortress, a room only eighteen feet square, and
intended only for confinement of two or three men.  This dungeon had only two sma'.l
windows, both upon one side of the building, in front of which was a verandah that aide!
greatly in impeding whatever slight circulation of air there might be.  Besides the gre. t
heat of a July night, on which this occurred, conflagrations were raging near the fort
which greatly increased the heat.  Very soon after the men were confined, the suffering
became intolerable, and the dungeon was a scene not only of the intensest anguish, b' t
of frightful delirium of most of the inmates. By eleven o'clock the men began to din
very rapidly, and owing to the intense heat and  overpowering stench caused by  those
exertions of the frantic soldiers, in the morning at six o'clock, when the doors were
opened, but twenty-three were alive, who were either stupefied or raving.
  46S. What does their delicate structure show us? 469. What is said  of the necessity
of action for the lungs ? What habit is of great service,  and why is it ?  470. IIow do im-
purities of the air affect the lungs? What kind of impurities are the most injurious?
What is one oi th* principal sources of disease in civilized society? 
AND  PHYSIOLOGY.
267
all combustible substances.   And it is  safe to  say, that the
greater the care we take to ventilate our rooms,  and in every
way to breathe pure air, the  longer shall we live and with
the least amount of pain and disease.   Breathing  impure air
is one of the greatest natural evils to which civilized society
is subject, and destroys more lives than  almost any other.
  471.—5.  We need  Pure Air  hy  Night as  well  as bj
lay.—Hence we see that the lungs need pure air all the time,
by night as well as by day—in the  sitting-room, the eating-
room, and the bed-chamber, the school-house, the meeting-
house,  rail-car, and steamboat, if we would do our  utmost to
ward off disease and death.
  472.—6.  Capacity  of the Lungs Affected  by  Posture.—
The capacity of the chest  is greatly influenced t by our posi-
tion in sitting  or  standing, and  the amount of  use to which
it  is subject.   If the shoulders  are  thrown forward  or  the
body is bent in the same way, the lungs  are compressed, and
can not be filled to their full capacity.  Hence  special pains
should be taken to maintain the body in  an erect posture, and
to keep the chest thrown forward.
  473.—7.  Pure  Air is often a Medicine.—In  most diseases
the breathing  of pure air is important for restoration to per-
fect health, since there are  often some impurities in the blood
or system which  are  removed  mainly by pure air.   So that
the rule  of  supplying pure and warm  air to the  sick room
should be rigidly observed.
  474.—8.  Warm and  Moist  Air  the  Best  for  a Healthy
Person.—The air best adapted  for  breathing should contain
but a small amount  of moisture,  nor should it  be perfectly
dry, especially that  which  comes from  intensely heated iron
surfaces.  Cold and damp air is apt to  bring on irritation of
the mucous membrane, producing coughs and colds.
  475.—9.  Capacity of the  Lungs may  be   Increased.—
 471. When and where do we need pure air?  472. IIow is the capacity of  the lunp
modified? What of the necessity of an erect posture in sitting or standing? 473. Why'i
pure air so important in sickness?  474. What is the best quality of  air for breathing ' 
2(38
HITCHCOCK'S  ANATOMY
The lungs, if compressed by disease or improper clothing, and
even in many cases of so-called perfect health and  soundness,
can be very much enlarged in their capacity.   This can  be
done by loud reading, or by the simple act of filling the lungs
with air to their utmost capacity several times each day, after
the manner mentioned under  inference  3d.   If this healthy
habit be kept up for a few years even by some considerable
effort, nature will at length take up the habit, and we shall
ultimately be found involuntarily filling  the lungs with pure
air, and thus fix upon ourselves a hygienic habit of great im-
portance in preserving health, and of great value in repelling
disease.
   476.—10. Colds  and   Coughs—Treatment—Sympathy
between the Different  Parts of the Mucous  Membrane —
Colds and ordinary coughs are affections of the mucous mem-
brane,  and generally only of the lungs, pharynx, and nostrils
and air  passages leading  to the  lungs.   They are  often pro-
duced by obstructions in the vessels of the skin, and hence a
great relief in  many instances for a cold, and often a cure, is
to remove this obstruction by  stimulating these  vessels  to
powerful action, as in sweating.  This effect is produced  by the
sympathy which exists between  the skin and mucous  mem-
brane,  one often performing the  function of the other for a
short time.   The mucous  membrane also has  a remarkable
sympathy between its different  parts ;  and hence even the
portions which are unaffected  by the cold should be kept  as
quiet as possible, by taking, for  instance, but little food into
the alimentary canal, and that of a liquid character, so that it
may be readily taken up by the absorbents of the stomach.
  477.—11. Injurious  Effects of Wearing  Shawls  b;.t
Gentlemen.—From  the fact  that whatever compresses the
chest greatly tends to bring on diseases  of the  lungs, we in-
 475. How can the size of the lungs be perceptibly increased ? 476. What are colds and
common coughs ?  How are they often induced ?  What is their best treatment? What
is remarkable about the sympathy between the skin and the mucous membrane? 477,
How are shawls often injurious to tbu lungs ? 
AND  PHYSIOLOGY.
2G9
fer that the wearing of shawls by gentlemen, inasmuch as it
requires a drawing forward of the  shoulders  to  make them
thoroughly cover the body, compresses the lungs, and there-
fore is highly injurious.  Moreover, it makes a person round-
shouldered, and  thus gives the appearance  of premature old
age.
  478.—12.  The Neck  to  be  Dressed  Lightly.—From
the many movements which are made by the larynx in speak-
ing, we infer that it is  a matter of great importance that the
neck in health should be always  loosely dressed.   For tight
cravats and neckcloths are  sure to obstruct the proper func-
tion of this organ, and bring  on irritation, which may end in
bronchitis or consumption.

  479.—13. A  Strong  Voice Demands  Vigorous  Exer-
cise  of  all the Body.—We learn also that they who would
have the strongest and best developed voices for speaking and
singing should pay special attention to the general health, and
particularly to muscular exercise  in the open air,  because the
voice  depends so  much more upon the healthy condition of
the whole body than it does  upon  the healthy or unhealthy
condition of the larynx.
  480.—14.  Great  Aid  in  Speaking can  be  Acquired
by Enunciating the Simple Vowel  Sounds.—Experience
shows  that great aid can be given to those who would secure
pure and correct tones in  speaking by slowly but distinctly
enunciating the simple vowel sounds of the English language.
This not only strengthens the organs,  but  it gives a proper
training  to  the laryngeal muscles, so that in the  composi-,
tion of vowels  and consonants the  muscles will  contract to
their proper amount, and only to  that.

 478. What clothing should be given to the neck ?  What is one source of bronchitis?
479. How is the voice made and kept clear and strong ? 480. How can poor .peakers
and readers make themsalves superior ones ? 
270
HITCHCOCK'S   ANATOMY
         COMPARATIVE  PNEUMONOLOGY.

                RESPIRATORY  ORGANS.

   481.  Trachea.—The Trachea in some animals, such as tha
 horse and  cow,  consists of complete rings, while in many ani-
 mals they  are  only portions  of  rings, whose  free extremities
 are united by membrane.   In man these rings number from
 seventeen  to twenty,  in the whale  from seven to twelve, in
 the carnivora from  thirty to forty, and in some  camels one
 hundred and ten.
   482.  Bronchi.—The Bronchial  Tubes  are  usually two in
 number, but in the ruminants, the dolphins,  and some other
 mammals  there are  three.   This  third tube  is  always the
 smallest, and passes to the right lung.
   483. Lungs.—In  the horse the  lungs are undivided, but
 in most quadrupeds the number  of lobes  is greater than in
 man.  In the marmot and hamster there are five in the right,
 and  three  c r four in  the  left lung.  In  the musk deer tho
 right lung is nearly twice the size of  the left.   The terminal
 «ur-cells of all  these animals correspond in bize very nearly
 with those  of man.  The lungs are proportionally  the largest
 in the  more powerful carnivora, and smallest in the weak
 herbivora, and the red blood corpuscles are much more abund-
 ant in the blood of the former than of  the latter.
   484.   Respiration of Birds.  Lnnglets.—In  Birds the
 respiratory apparatus, like that of Insects, extends through a
 large part of the body, (Fig. 264, p.  271),  not only in tho
 lungs proper, but through the channeled  bones which are lined
with a membrane for purifying the blood. (Fig. 265, p. 271.)
 481.  How does the trachea in many of the lower  animals differ from that of man ?
What is the relative number of rings in each ? 482. What is said of the number of tha
principal bronchial tubes ? 483. What of the number of lobes ir many quadrupeds? In
what animals are the lungs largest and in  what ones weakest? 484. How is the respir-
atory apparatus of birds and insects alike? 
AND   PHYSIOLOGY.
271
Fig. 264.
Pulmonary Vessels. —


            Lung. _.

 Bronehic Orifices. -
Bronchus laid open.
Bronchus laid opes.
Lungs of a Bird.

  FiG.  265.
  Pulmonary Apparatus of a Pigeon, as seen on removing the Anterior Wall of the
Thorax,  a. Trachea.   6.  Bronchi,  c. Lungs,  d. Apertures of Commanication
with Air-Cells.
                                  12* 
272
HITCHCOCK'S  ANATOMY
Large air-sacs are also contained  in the abdomen, freely com-
municating with the lungs, and acting as reservoirs for them.
A minute examination of the structure of these organs shows
Fig. 266.
 Lunglet of a Fowl.  A. Section passing in the direction of the Bronchus. B. Seo-
tion cutting it across.
Fig. 267.
  £ungs of Frog.  a. HyoH Apparatus.
I. Cartilaginous Ring.  c. Longs Proper.
that they are made up of lo-
bules  or  lunglets,  each  of
which has its own system of
vessels,  and  but little com-
munication  with   the  other
lunglets.
   485.  Lungs of  Reptiles,
— The Hiss of Serpents.—
Mechanism   of   Respira-
tion.—The  Lungs of  the
several orders of Reptiles are
for the most part  capacious
sacs, the extent of surface in
which is but little increased
by  smaller  sacs  or vessels
within  them.   In  the Frog,
 What appendages do they have which do not exist in quadrupeds ?  485. What are the
lungs of reptiles? 
~VD  PHYSIOLOGY.              273

         Fig. 268.
   Lungs of Serpents,  a. Trachea, b. Bronchi,  c. Eight Lung, c'. Left Lung.
  d. Pulmonary Artery.

for example, the bronchi terminate in capacious  cavities, upon
the sides of which are the pulmonary blood-vessels.   In many
serpents the pulmonary apparatus consists of a long  cylindrical
sac or lung upon the right side of the body, the  corresponding
one on the left side  being merely rudimentary, as seen in Fig.
268.   Serpents are capable of expiring  and inhaling large
quantities of air,  which compensates for the want  of  a great
internal  surface of lungs.   And  the peculiar  hiss made by
them is simply a prolonged expiration of air  from  the lungs.
How is it in frogs and serpents? What makes the hiss of serpents ? 
27 i           HITCHCOCK'S  ANATOMY
Fig. 269.                          Fig. 270.
Lung of Turtle laid open.          Gills of Eel. A. Enlarged Portion.
In aquatic serpen^aCthe amount  of air  contained in the body
tends to make it  buoyant, and  at the same time supplies the
wants of the animal during a long immersion.   In frogs and
many of the class reptilia the air is forced into the lungs by
a process similar to  that of  swallowing.   Taken as  a whole,
this order is remarkable  for the  feebleness of its  respiratory
actions,  and the length  of time which the function  can be  sus-
pended without injury.   The temperature in which  the  ani-
mal lives, however, greatly modifies the amount of air exhaled
and inhaled.
   486.  Gills  of  Fishes. — The  Respiratory  apparatus of
Fishes  consists of Gills  for procuring  the  air contained in
water.   The Gills are  fringes of minute bronchial tubes  sus-
pended from  cartilaginous and bony arches,  that are  situated

  How do frogs inspire ?  What efiect has the temperature upon the respiration in uifl
•lass of animals? 486. What are the organs of respiration in fishes?  Describe the gills. 
AND  PHYSIOLOGY.
275
just behind the lower jaw.   "These are disposed, in most
fishes, in fringed laminae, which are set  close together like
the barbs  of  a feather, and  are  attached on each  side  of
the throat in double rows, to  the convex  margins of four or
five long, bony, or cartilaginous arches, which are suspended
from  the hyoidean arch."

  487. Air-Bladder .—Another organ which perhaps claims
attention here, is the Air-Bladder.   This is a small shut sac
—sometimes nearly subdivided  into two  or more sections  by

                         Fig. 271.
 Air Sac of Fish (Carp),  a. b. A Divided Form. c. d. A Tube connecting it with
the Esophagus o.

a membranous division—which lies near  the  middle of the
back.  In most cases it has no connection  with any other or-
gan, but sometimes has an opening into  the esophagus or
stomach.   The uses for which it has been  supposed to exist,
are to enable the fish to alter its specific gravity, and also to
aid in respiration in some manner.   It has also been conjec-
tured that it aids the sense of hearing, since it is in direct
connection  with  the auditory apparatus.   It  is filled with
atmospheric air, with greatly  varying proportions of oxygen
and nitrogen.  Some fishes that leave the  water occasionally
and crawl over the land, have a cavity in the side of the head
for water, which is in contact with a respiratory apparatus,
and thus the fish can live for some time out of its native ele-
ment.—Wyman.
 487. Describe the air-bladder.  What does it sometimes communicate with ? Give
its probable uses.  What is it filled with ? 
276
HITCHCOCK'S  ANATOM
  488.   Trachea  of  Insects—Spiracles.—Mechanism  of
Respiration.—Wisdom  of  this  Arrangement.—The  res-
piratory vessels of  Insects are  analogous to those  of birds
in  that they  extend  through  a large   part  of  the body.

                           Fig.  272.
  rrachea of Water-Scorpion,  a. Head. 6. First Pair of Legs.  c. First Segment ol
thorax, d. Second Pair of wings,  e. Second Pair of Legs.  /. Tracheal Trunk,  g. One
of the Stigmatte. h. Air-Sac.

The essential  organs are Tracheae  or air-vessels, which open

upon the sides of the body, and freely communicate with one

another.   Air sacs are found in the  front parts  of the  body

  483. What are the essential organs of respiration in insects ?  Whereabouts in the ani-
mal are the trache® found ? 
A X I)  r II Y S I O L 0 G Y .
277
of some insects, and  the  tracheae are very minute, ramifying
through  the most delicate  organs of the  body, which  plan
allows a  rapid aeration of the blood, and  greatly assists in
diminishing the specific gravity of the animal.   The openings
upon the surface of the body are called Spiracles or Stigmata,
and  are  either oval or  made in  the shape  of a slit, as is
seen in the adjoining cut.   In the soft-skinned insects  they

                           Fig. 273.
Spiracle of Common Fly.
are surrounded by a ring of cartilage, to prevent their closing
by ordinary accidents or pressure, and  all spiracles  are  pro-
tected  by a kind of  sieve or grating,  made  up of hairs ex-
tending from  either  side  of the aperture,  which keeps out
dust, that would  otherwise  enter with the  air and stop the
passage.   The interchange of air is effected  by the enlarge-
ment and contraction of the abdomen.   The  rings, (or skele-
ton), which surround  the  abdomen, are seldom inflexible, but
ere made up in one part of membrane,  and the  horn-like ends
are brought  together by  muscular  contraction,  by which
means  expiration  is  effected.    The enlargement  or inspir -
tion is accomplished  by the simple elasticity of the encasing
rings  of the body,  as well as of the  trachea.   Hence,  full-
ness is the natural or  passive  state  of the respiratory or-

  What are the spiracles? How are they sometimes protected? Give tho mechanism
of respiration. 
278
HITCHCOCK'S   ANATOMY
gans, as was seen  to be the case with  birds.   Still another
way in which respiration is effected, is by t!.e sliding of one
ring inside the next one, like  the joints  of a hand telescope,
and their return by the elasticity of the tissues of the body.
And we can not  fail to observe the  beautiful design of the
Creator, when, though he  furnished but a limited circulation
of fluid, yet fully compensated for it by introducing the air in
minute tubes to the very center of every tissue.

   489. Crustaceans.—These animals breathe mostly by gills.
The Myriapods have proper tracheae, though with some respi-
ration is chiefly cutaneous,  that  is,  directly through the skin.
The Arachnoid  or  Spider tribe  sometimes have tracheae and
sometimes even lungs.   The gills of the  Crustaceans are situ-
ated in different parts  of  the  body, more especially on  the
feet.

   490. Molluscs.—In the  Acephala the blood before return-
ing to  the  heart  passes through a bronchial organ  or gill,
which  opens and  closes  for the ingress and  egress of water.
Some of tlie Cephalophora have gills; others lungs, and others
a system for the circulation of water containing air,  through
different parts of the body.  The Cephalopoda all respire by
gills;  but they have also an aquiferous system.

   491. Radiates.—"The  simple exposure of the surface of
a jelly-fish  or polyp to  the action  of the fluid around it is
sufficient to carry on all the changes which take place in its
simple kind of respiration."—Prof. J. Wyman.   Nearly all
the Radiates  have  such an  aquiferous  system.   But  many
of them have other organs for breathing.  The Fchinoderms
have  gills;  also sometimes their  organs of  prehension and
locomotion form a respiratory apparatus.
 What instance of compensation is shown here ? 483. Do any crustaceans hreathe by
gills ?  490. What is the breathing apparatus of molluscs ? 491. What is tha respiratory
apparatus of radiates ? 
AND  PHYSIOLOGY.
279
           TIIE SOUNDS PRODUCED BY ANIMALS.

  492.  Among vertebrates the production of vocal sounds is
confined to the air-breathing  classes,  since no  fish or gilled
animal  is able to make  any sound by means of the  special
organs which are provided for that purpose in other animals.
  493.  Laryngeal  Pouches,  or  Sacs.—Nearly every mam-
mal  can make some vocal sound, and the structure of the
larynx in all very closely resembles that of man.  The howl-
ing apes present the most striking difference in these organs.
They have  pouches, or  laryngeal  sacs a3 they are  called,
connected with the  larynx, which  increase  the loudness of
the voice simply by the resonance of the voice in these cavities.
  494.  The  Two Larynges of Birds—The  Trill  of  Birds.
-—In birds the vocal organs are somewhat different from those
of man.  There is  in them a  larynx, called  the superior
larynx, at the  summit of the trachea,  which  seems designed
mainly  for  the  ingress and egress of air.   But  the vocal
sounds for which birds are so remarkable  are made by what
is called the inferior larynx, which is  situated at the lower
extremity of the trachea.   This  is  most  complex in birds
which  have the  greatest powers of song.   The two or three
lower rings of  the trachea  are usually consolidated into one,
and in the interior a cross bone runs from front to back which
has upon its upper edge a small  membrane of a crescentic-
shape,  which is so lax that  it can freely vibrate when the air
is made  to pass  rapidly  over it.   This in  its action, is anal-
ogous to the reed of the  clarionet  or melodeon.   It is by the
vibration of this membrane that the  peculiar trill of many
singing-birds is so beautifully executed.  The intensity of the
 492. What rertebrates alone can make vocal sounds ? 493. What is said of the struc-
ture of the larynx in all mammals ?  Wliat is the peculiarity among the howling apes ?
494. How many larynges have birds?  Give the function of each. What peculiarity in
the lower part of the trachea ? 
280
HITCHCOCK'S  ANATOMY
tune is greatly increased by the  construction of the trachea
and  bronchi.   "Birds  whose voices  have a  very extensive
musical scale are able to shorten and  lengthen their wind-
pipe considerably, and to that end have very thin wings and
large membranous interspaces."
  495.  Larynx of  Reptiles.—Reptiles  have an  imperfect
kind of larnyx, which is located at  the point where the tracheal,
opens  into  the pharynx.   The only  sounds which  they caq
make is the croak of the frog and hiss of the serpent, turtle,
or lizard.   The common Frog has two vesicles or little bags
behind the angle of  the mouth, which are much distended at
the beginning of summer and at pairing time, which accounts
for their loud croaking at these seasons.
  496.  Sounds Made by Insects.—As we descend the scale
of animals, we find  in  no other a larynx  or organ of voice,
and  hence all  the sounds made by them  are  not  the sounds
of the voice, but  simply noises which are  for the  most part
made by their extremities.   The sounds made by insects such
as approach most  nearly to those of vertebrate animals,  are
produced  by vibrations of a membranous  plate  situated just
over the spiracles.   And  in general those  insects that fly  the
most rapidly, and whose  wings move  the fastest,  make  the
most noise, while those which move more slowly seem only to
fan the air with their wings.   Other sounds are produced by
mastication.   Thus,  an army of locusts, when eating, makes a
sound which very much resembles the noise of a crackling fire.
A genus of ants make a  sound by striking some  hard sub-
stance  with  their mandibles, or  arm-like appendages.    A
species of beetle that bores in old timber (called  the death
watch) makes a sound in  a similar way, and if it be answered
by its mate the signal will be  repeated :  but if  no  answer be
given, the animal  changes its position  before  it produces its
" tick''  again.   The shrill sound  of the grasshopper and the
 What use is it? What construction increases the intensity of their tones ? 495. What
is the larynx of reptiles? What is their voice?  496. Do  insects have  a larynx? In
what different ways are sounds made by insects ? 
AND  PHYSIOLOGY.
281
so-called locust is made by rubbing together the anterior pair
of wings, upon the nervures  or framework of the wings, on
which  are  found file-like edges.  In a large  species of this
kind living in Brazil, which has a drum-like appendage un-
der the wings, the sound can  be  heard a mile;  and if a man
of ordinary stature possessed a proportionably loud voice, he
could be heard all over the world.                           *
  497. Sounds  of Mollusca.—Among the CephaJopods there
are a few individuals which are able to make a clear,  bell-like
sound, but the origin ofit is unknown.
49T. What is said of sounds made by molluscs ? 
CHAPTER   SIXTH.
ICHOROLOGY, OR HISTORY OF THE  ORGANS  OF SECRETION.
         THE LYMPHATIC AND SECRETORY SYSTEM.
DEFINITIONS AND  DESCRIPTIONS.
  498. The  Body is Constantly Undergoing a  Change.—
We have seen that the  human body is constantly undergoing
              Fig. 274.               changes in its  constituent
                                    parts.   The nutrient por-
                                    tion  of the food designed
                                    for the support and growth
                                    of the different  tissues is
                                    conveyed by the lacteals to
                                    the left  sub-clavian vein,
                                    where it enters the general
                                    circulation; while the par-
                                    ticles which are constantly
                                    set free in all  parts of the
                                    body are, by vessels of the
                                    same  general   character,
                                    called  lymphatics,  con-
                                 ,1''• veyed to  the  blood  and
                                J"  thence to the lungs.
                                       499.  The  Lacteals   a
                                    Variety of the Lymphat-
                                    ics.— A  more   correct
  A, a, Deep-seated Lymphatic Gland, a, b, Lym-                  ,
 phatics which supply and Empty the Gland, b arrangement,    however.
 a, Superficial Lymphatic, less complex in struc- \\yln rrs both sets of absOrb-
 ture.   c, a, Lymphatic laid open to show the      o
 Valves, c, d, e.                          ent vessels under the class
 of lymphatics,  making  the lacteals  only a variety, since their
  49S. How is it that the body is constantly undergoing change ? 499. What may th«
 lacteals be properly called ?
 
A X  li   p II Y S I O L O G Y






           Fig. 275.
2_.
The Lymphatics of the Body, 
284-             HITCHCOCK'S  A N A T O M V

chief  difference consists in the  kind of material  they convey,
and not in structure or function.
   500.  The  Lymphatics—Their   Similarity to  Veins  and
Arteries—Their Appearance when  Injected with Mercury.
—The lymphatics  are very delicate, minute  and transparent
vessels like the capillaries, remarkable for  their uniformity of
                              Fig. 276.
  A View of the Vessels and Lymphatic Glands of the Axilla.  1, The Axillary ArU ff.
2, The Axillary Vein.  8,  The Brachial Artery.  4, The Brachial Vein.  5. The Primi-
tive Carotid Artery.  6, The Internal Jugular Vein. 7, The Sub-Cutaneous Lymph.it
ics of the Arm at its Upper Part.  8, Twoor three of the most Inferior and Superficial
Glands into which the Superficial Lymphatics emnty.  9, The Deep-seated Lymphatics
which accompany the Brachial Artery.  10, The Lymphatics and Glands which  accom-
pany  the Infra-Scapular Blood-Vessels.  11, The Glands and Lymphatics accompanying
the Thoracica Longa Artery.  12, Deeper-seated Lymphatics.  13. The  Axillary Chain
uf Glands.   14, The Acromial Branches of the Lymphatics.  15. The Jugular Lymphatics
and Glands  16.17, The Lymphatics which  empty into the Sub-Clavian Vein near ita
Eunction with the Right Internal Jusnlar Vein. 
A X D   PHYSIOLOGY.                2So
Fig. 21
size, of a knotted appearance, and very frequently dividing into
two nearly equal branches.   Like veins and arteries, thoy have
three  coats,  with folds of the
inner  coat for  the  formation
of valves,  giving them a knot-
ted appearance.   They  com-
mence  in a minute net-work
i i nearly every organ of the
body,  and soon unite into  a
few large  trunks  which take
a direction towards the  veins
in the lower  part of the neck.
This  net-work is so  exceed-
ingly delicate,  that when filled
with  mercury it presents the
appearance of a sheet of silver.
The necessity  of such an im-
mense number of these vessels
arises from the constant lib-
eration of the  waste particles
of  matter which  need  to be
removed as  soon  as possible,
that  the  deposition  of  new
particles may not be prevented.
   501.  Lymphatic Glands.—
As  the   minute  lymphatics
unite into larger trunks, they     A  view  of the Eight Lymphatic Tho-
                                   racic Duct.  1, Arch  of the  Aorta.  2,
Thoracic Aorta.  3,  Abdominal Aorta.  4, Arteria Innominata.  5, Left Carotid.  6,
Left Sub-Clavian. 7, Superior Cava. 8, The two Venae  Innominatae. 9, The  Internal
Jugular and Sub-Clavian Vein at each side. 10, The Vena Azygos.  11, The Termination
of the Vena Hemi-Azygos in the Vena Azygos.  12, The  Keceptaculum Chyli : several
Lymphatic Trunks are seen opening into it.  13, The Thoracic Duct dividing,  opposite
the Middle Dorsal Vertebra, into two branches, which soon re-unite ; the course of the
Duct behind the Arch of the Aorta and Loft Sub-Clavian Artery is shown by a dotted
Line. 14, The Duct making its turn at the Root of the Neck and receiving several Lym-
phatic Trnnks previous to terminating in the Posterior Angle of the Junction of the In-
ternal Jugular and Sub-Clavian Veins. 15, The Termination of the Trunk of the Lym-
phatics of the Upper Extremity.
 500. Describe the lymphatics.  How many coats have they?  What is said of the net-
wrork which they make ?  Why the necessity of such a multitude ?
 
286            HITCHCOCK'S   A X' A T O M Y

pass through small bodies, varying in size from a mustard-set d
to a pea, which  are called lymphatic  glands, whose design  h
not yet clearly understood.   They then pass upwards towards
the heart as already mentioned, those of the left side of the body
emptying themselves through the thoracic duct, while those of
the right side enter a tube running  parallel to this,  called the
Ri^ht  Lymphatic Duct, is, Fig.  277.

                              Fig. 278.
  A Front View of the Femoral, Iliac, and Aortic Lymphatic Vessels and Glands.  1, Sa»
phena Magna Vein. 2, External Iliac Artery and  Vein. 8, Primitive Iliac Artery an!
Vein.  4, The Aorta. 5, Ascending Vena Cava.  6, 7, Lymphatics which are alongsioj
of the Saphena Vein on the Thigh.  8, Lower Set of Inguinal  Lymphatic Glands which
receive these Vessels.  9, Superior Set of Inguinal Lymphatic Glands which receive thesa
Vessels.  10, The Chain of Lymphatics in Front of the External Iliac Vessels. 11, Lym-
phatics which accompany the Circumflex Iliac Vessels.  12, Lumbar and  Aortic Lym.
phatics.  13, Afferent Trunks of the Lumbar Glands, forming the Origin of the Thoracis
Duct.  14, Thoracic Duct at its commencement.
501. Describs the lymphatic glands.  What is the right lymphatie duct? 
A H D  PHYSIOLOGY.
287
   502. Material  Absorbed  by  Lymphatics —Effect  of
Various    Substances   Ap-              fig. 279.
plied to the Skin—Nutri-
ment  Sometimes  Intro-
duced  through  the  Skin —
Thirst  Quenched   by  Wet
Clothes.—These  vessels  not
only remove useless particles,
but absorb  substances applied
to the  skin,  although  some
maintain  that this i-i done by
the veins alone.   And this is
sometimes an effective method
of  administering   medicines
which  it  is not  expedient to
introduce through the mouth
and nostrils,  thus  producing
a desired effect upon  the  cir-
culatory and  venous systems
without offending, or in  any
manner affecting the senses or
feelings of the person taking
the medicine.   For instance,
spirits  of  turpentine  rubbed
upon the hands of many  per-
sons, and green  leaves  of to-
bacco  placed  upon  the  ab-
domen,   will   often  produce
                                   A Front View of the Deep-seated Lym-
phatics of the Thigh. 1, Lower End of  the Aorta.  2, Primitive Iliac Vein. 3, 4, Ex-
ternal Iliac Artery and Vein.  5, Femoral Artery.  6, Section of the Femoral Vein. 7,
Vena Saphena on the Leg.  8, Lymphatics near the Knee.  9,  Lymphatics accompany-
ing the Femoral Vessels. 10, Deep Lymphatics going from the inside of the Thigh o
the Glands in the Groin. 11, Lymphatics of the External Circumflex Vessels. 12, Lym-
phatics on the outer side of the Femoral  Vessels.  13, A Lymphatic Gland always found
outside of the Vessels.  14, A collection  of  Vessels and Glands from the Internal Iliac
Vessels. 15, The Lymphatics of the Primitive Iliac Vessels.
 502. What do the lymphatics absorb ?  What value of this fact at times ?  Give a com-
mon. effect of tobacco and turpentine rubbed upon the skin.
                            13 
_88
HITCHCOCK'S  A X A T O M Y
distressing  sickness.  Mercury, too, rubbed vigorously upon
almost any  part of the skin, will in a short time produce sali-
vation, because tin "jinute globules of this  metal are forced
through the pores of the skin, and are  absorbed by the lym-
phatics.   In  some  cases where  disease  has so  affected  the
mouth or  passage  to the stomach  as to prevent the intro-
duction  of  food, life  has been maintained for  a considerable
time by  nutriment introduced through the  skin, by means of
a bath of warm milk.   Shipwrecked  sailors in  an open  boat
and deprived of fresh  Avater, can for some time partly assuage
their  thirst by wetting their clothes with  salt water, or better
still, by a thorough Avetting during a rain storm.
   503.  Poisons  Introduced through  the Skin  by  the  Lym
phatics.—The poisoning which  frequently occurs  from  the
contact  of the  skin with sumach or ivy, is  owing to  the  ab-
sorption  of poisonous influence by these vessels.   Animal poi-
sons, too, such as the venom of mad  dogs, serpents,  and  in-
sects, are introduced to the general system by the lymphatics.
   504.  Pressure Increases their Action.—Pressure  greatly
increases the  action of the lymphatic Aressels.    This  is seen
in a broken  limb which has been  tightly bandaged, when  the
muscles become very small from the removal  of  the tissue by
the excessive action of the lymphatics.
   505.  Venous Absorption — Radicles.— Besides  lymphat-
ics, the small  veins perform the function of absorption.  It is
easily seen that these can perform the same office as the lym-
phatics, since both of them carry their fluids to  the  heart  for
purification, and  no other use  is made of them  on their way
thither.   These radicles, or small veins, perform a  very im-
portant function in the stomach by the rapid absorption of tb_
Avatery portion of all  liquids, and  its conveyance to the gen-

 Is nutriment ever conveyed into the system in this way ? Can thirst be quenched in
this way?  503. Do the lymphatics ever introduce poison into the system?  504. How
does pressure affect the action of lymphatics?  What example of it?  505.  What is taid
of absorption by the veins? What important service do  the radicles perform in tha
ptomach ? 
A X I)  PHYSIOLOGY.
289
eral circulation Avithout passing through the circuitous course
taken by the food.
  506.  Effect of Moisture upon tne Lymphatics.—Moist-
ure stimulates these absorbent vessels  to  a morbidly vigorous
action.   Hence a person surrounded  by a moist atmosphere
or immersed in  water itself, will acquire additional weight.
And as an excessive use of  the eliminating organs of the sys-
4:m is injurious,  locations for houses should be selected as lav
as possible on dry places, and not on wet  or low land Avhere
heavy fresh water  fogs prevail.   For  the same  reason damp
clothing injures  the body,  because it unduly stimulates the
lymphatics.
   507. Amount  of Matter taken up by  the Absorbents.—
The amount of Chyle and Lymph poured  into the blood by
the lymphatics and  radicles h about  one  third of the whole
amount in the body.


              ORGANS  OF  SECRETION.

   508. Follicles and Glands.—Character of Secretions-
Size of Follicles.—The organs  which perform  the office of
secretion in the body  are Follicles and  Glands.   The former
of these are small bodies in the form  of sacs or  tubes, exist-
ing  for the most part in the skin and mucous membrane, one
end of Avhich opens upon the surface of the membrane, for the
discharge of its secretion.  The  secretion  poured from these
varies in consistency  from the thick  Avax of the ear, to the
limpid juice of the  stomach.   The  follicles vary also  in  size
from tubes perceptible to the naked eye down to those -^th of
a:i inch in diameter.
   509. Glands.—The Glands are soft solids of  various sizes
(the liver the largest) made up of lobules  or small bodies of
  506. How does moisture affect the lymphatic action ? How do damp clothes injure tho
wearer? 507. What is the amount of matter taken up by the absorbents?  508. What
is the anatomy of the follicles?  Of what c.i_i_aer is their  secretion?  What is thev
size ?  509. What is a gland ? 
.90
HITCHCOCK'S  ANATOMY
Fig. 280.
Intimate Structure of a Gland (the Parotid).
minute proportions, each of Avhich has an  artery, a vein, and
a duct to carry aAvay the secretion.   These  ducts  unite with
one  another,  until  they form  one tube  called  the principal
outlet of the organ.   In some glands these  lobules are quite
                    Fig. 281.

Aorta. Thoracic Canal.  Lymphatic Oanglions.
  1
Radicles of the Chyliferous
  Vessels.
Lymphatic V.-ssels.  Mesentery.
                       Chyliferous Vessels. 
           ANATOMY  AND  PHYSIOLOGY.       291

large—one fourth of an  inch in diameter—while  frequently
they are nearly the size of a mustard seed.  The color is also
various.   That of  the liver  is a dark  red, the pancreas of a
pale white or gray, the little gland in the inner angle  of the
eye pink, and the kidneys a  reddish yellow.

   510. Function  of  Secretion.—The function performed by
these  vessels is an exceedingly curious, and  not easily ex-
plained phenomenon.   For  from the blood  are eliminated by
the various  secretory organs, bile, saliva, perspiration, tears,
etc., none of which exist there as such, but they seem to be
formed from the chemical elements in the blood by the glands
themselves.
   511. Effect  of  the  Emotions  upon the  Secretions.—
The mental  emotions  greatly affect  the secretions.   A person
in fear is often covered with a cold perspiration, and in some
persons in the same situation the salivary glands cease to act.
On the other hand the thought of savory food has been known
to cause the saliva to issue in  a jet from the  sides  of the
mouth.
   512.  Reserve Glands.—Some glands also act only on parti-
cular occasions, as in the case of a broken bone, or cut in the
flesh,  when  the appropriate vessels  set themselves  at work to
repair the injury.
   513.  Secretion after Death.—Certain secretions are con-
tinued for a time after the death of the  individual.  Thus it
has been observed that  the  hair and nails grow considerably
after death,  provided   the disease was a rapid one,  so that the
system Avas  not reduced by loss or degeneracy of the blood
and nervous system.   It is also related that in dissecting the
poison apparatus  of a rattle-snake, the poison Avas secreted so

  Give the minute anatomy of the glands.  Describe their ducts.  Mention their various
colors. 510.  What is the use of the glands? Do the secretions exist ready formed in the
blood?  511. What is the effect of the'feelings upon secretion?  Give an example.  512.
What is said of reserve glands? 513. What i» said of secretions continuing some time
after death ? Give an example. 
292
HITCHCOCK'S  ANATOMY
fast that it was necessary to dry it off occasionally during tho
dissection.
  514.  Vicarious  Secretion.—Another curious  phenomenon
connected with this subject is  vicarious secretion,  where one
organ performs the Avhole or  part  of the office of another.
This is often seen in the function of the lungs and liver, where
one imperfectly performing its office, is  aided by  the  other.
This vicarious secretion is still more apparent  between the
liver and skin.  For in the disease known as Jaundice,  where
some obstruction is offered to the passage  or secretion of the
bile, it is poured out  by the skin, coloring it deeply yellow,
and in some instances it has been  knoAvn to stain  the linen,
Avhich is Avorn next the skin,  perceptibly yellow.
  515.  Ductless  Glands.—In  connection with  this subject
it is proper to mention  a class  of organs  known as Ductless
Glands, or bodies which have the form and  general structure
of glands,  but no duct or  outlet, and form no secretion, as do
the true glands.   These  are the  Spleen, the  Thymus  and
Thyroid Glands, and the Supra Renal Bodies.  Of these only
the former will be described here, since  the  latter are most
perfectly developed during the earliest, or  fetal stage of exist-
ence.
  516.  The Spleen.— The Spleen measures in different indi-
viduals from four to six inches  in its longest diameter, and  is
situated under the  left extremity of the stomach.   (Fig. 282,
p. 293.)  It is of a reddish blue color,  convex on its external,
and  concave on  its internal  surface.   It  is  very abundantly
supplied  Avith  blood-vessels,  and  consequently vascular or
spongy in its structure.    (Fig.  283,  p. 293.)   Upon a close
inspection it is found to be  made  up of corpuscles from oi 9
third to one sixth of a line in diameter, each of which is com-
posed of nucleated cells about   j "Votb of an inch in  diam-
eter.   (Fig. 284, p. 293.)
  514. State the principle of vicarious secretion  What remarkable facts in thisconnec>
tion about jaundice?  515. Describe the ductless glands.  What are their names? Al
what period of life are they tho most fully developed ?  516. Describe the spleen. 
AND  PHYSIOLOGY.
293
Fig. 282.
Fig. 283.
Section of the Spleen.
  Shows the Internal Face of the Spleen
where it touches the Stomach.  1, Supe-
rior Extremity.  2, Inferior Extremity.  3, Posterior Part of the Concave Face.  4, An«
terior Part of the same.  5, Fissure of the Spleen.  6, Splenic Artery.  7, Splenic Vein.
8. 8, Anterior Edge of the Spleen.  9, 9, Its Posterior Edge.

                                   Fig. 284.
Section of the Spleen magnified. 
294            HITCHCOCK'S  ANATOMY

  517. Function of  this Organ.—Produces  and  Destroys
the Red Blood Corpuscles.—As already  stated  there  is  no
duct or outlet to this organ, or evidence of any secretion out-

                           FiG. 285.
  Small Portion of the Spleen very highly magnified, showing two corpuscles and the
minute Blood-Vessels.

ward.   But  the idea has  occurred  to physiologists, though
with no positive proof as yet, that a kind of secretion is pro-
duced  by the spleen which is poured directly into the  blood,
and consequently there  is no necessity for  any outlet.   And
again experiments have been carried so far as to give plausi-
bility  to  the idea, that this  organ is designed to produce
blood corpuscles, and at the same time use up those  that are
 517. Of what use is the spleen ? What is said of it as an organ for producing blood
cornuscles ? 
AND  PHYSIOLOGY.
295
no longer of service  to the body.   Certain it is that no other
organ in the body has as yet been discovered which  subserves
this purpose,  and equally certain  that  in  cases, where large
wounds are to be  healed, and  in  certain  other conditions of
the body, the  white corpuscles are greatly  increased  in  num-
ber.

   518. The Skin.—Among those organs whose offices are
those  of absorption and secretion, the Skin finds a prominent
place.
   519. Made  up of Three  Membranes.—This is a membrane
simple  in its  general aspect, but under the microscope it  is
found  to  be composed of no less  than three distinct layers:
the Epidermis, Basement Membrane, and Corium.   It covers
every part of the body, except the portion immediately sur-
rounding the various orifices, and those portions of the ex-
tremities covered by the  nails.  It is  highly elastic, as may
be seen by the gaping of a long gash, and  possesses  a certain
amount of contractility, owing  to  some muscular fibers con-
tained in  it.

   520. Papilla;; their Size.—Upon several portions  of the
body  the skin  is  roughened  by small protuberances, either
arranged  in a circular form, or in rows, Avhich are supplied
with  one or  more  loops  of
nerves.   These  are termed              Fig. 286.
Papillae, and are found most
abundantly  in the  extremi-
ties, and  especially upon  the
palms of  the hand and soles
of the  foot.  They  vary  in
height from ^rd to ^d of a
line, being of different lengths    fled thirty-five times.
in different parts of the body.

 519. Of what three membranes is the skirt made up? State their general proper-
ties. 520. What are the papillae?  Where are they found in the greatest numbersI
State their size.
                            3*
Papillre from Palm of the Hand, magnl- 
296
HITCHCOCK'S   ANATOMY
   521. Epidermis or Cuticle;  Has  no Vitality.—Pigment
Cells.—Composition  of Pigment-Cells.—The outer layer of
the skin  is called the  Cuticle or Epidermis, and  bears the
same relation  to the true skin,  that the outer bark of the tree
does to the inner.  In thickness it varies considerably in the
different parts of the  body.   It is yloth of an inch thick on
the chin,  cheeks  and brows, and yLth  to £th of an inch thick
on the soles  of the foot.   It is merely a layer of albumen—
FiG. 287.
FiG. 288.
&:~.b
 Vertical Section of Epidermis from a
Negro,  a, Deep  Cells loaded with Pig-
ment, b, Cells more elevated and some-
what flattened, c, Scaly Cells at the Sur-
face.
 Highly magnified Pigment-Cells.  A.
Scales of the Epidermis filled with Pig-
ment Cells which are seen separate at b.
B. Pigment Cells from the Choroid Coat
of the Eye.
the same substance as  the while of an egg—and is secreted
by  the  true skin, in the form  of scales, which  are closely
compacted together, and it is in this form  that they are de-
tached  from the body  by washing and  friction.   In some
cases, however, it is detached in large patches, so  that aftei
certain  skin diseases have run their career, the  whole  epider-
mis of the hand with the nails  adherent maybe  removed in
the manner of a glove.  The  epidermis contains  no blood-
vessels  or nerves, and consequently no vitality, it being merely
a secretion which  hardens into a semi-transparent membrane.
A part  of the cells of the true skin, however, instead of se-
creting the epidermis, produce  what  is termed the Pigment
  521. Describe the epidermis. To what does it correspond in the tree ? State its thick-
ness and chemical composition.  What vessels and what cells does it contain? Whera
ire the pigment cells shown ? 
AND  PHYSIOLOGY.
291
Cells, which give color to the skin.  These cells  are  best ex-
hibited in the eye where the pigmentum nigrum (black paint)
is secreted,  and are of the same kind with those in  the epi-
dermis.  They are  oval  or  rounded  granules,  measuring
"swoirth  0f an jnca jn diameter, and one quarter of this in
thickness, sometimes presenting a ponygonal or stellate form.
They have nearly the same composition as the coloring matter
of the cuttle-fish, which contains a much larger proportion of
carbon than is contained in most organic substances, namely
58j  parts in  hundred.  The development of these cells de-
pends mainly upon exposure to the sun's light.  Hence we
see that  persons with a fair  skin become of a darker hue, if
exposed  to  the strong and direct light of the sun.

   522. The Nails; Mode  of  Growth; Rate  of  Growth.—
The Xails are composed of the same material as the epidermis,
being merely  an  altered form of it.  When their newest por-
tions aie examined with the microscope, they are found to be
nucleated  cells closely  resembling  those of the epidermis,
Epithelium cells.   The
nail increases in  length
by successive additions
to its root,  which push
it forward over the end
of the finger,  while  at
same  time  it receives
additional layers from
the skin  beneath.   The
nails of the hands grow
about two  fifths of a
line  per week, while
those  of the  foot re-
quire four times that period for the same amount of growth.
The  blood-vessels  of the nails are very abundant, and are

  What is very remarkable about the chemical composition of this pigment? What
does the development of these cells depend on? 522. Of what composition are the nails?
Of what kind of cells are they ?  How fast do the nails of the hand grow ?
FiG. 280.
 Section of the Thumb, a. Last Bone of the
Thumb,  b. Epidermis reflected on the Nail.  c.
Nail.  d. Epidermis at the Point of the Tumb. 
_98
HITCHCOCK'S  ANATOMY
situated just within the  corium,  into which the  nail barely
dips.   And so numerous are these, and of so low  a degree of
vitality,  that frequently the nails grow  for a  short  distance
after death.  When the nails are  badly injured, they are sel-
dom perfectly regenerated, because  of the  injury  done to  the
vessels and laminse.  A rudimentary nail sometimes is found
on the second joint, when the first  is destroyed.   Cases  are
a'so on record,  where the nails  have been  shed and  renewed
periodically.   The nails  are thickest at their most  convex'
portion, instead of their edges, and increase in  thickness from
the base to their free edge.   They grow  only so long as they
are cut,  and among the literary class  of the Chinese, who
never cut their nails, they are said to attain only a length of
two inches.   The  time  necessary for a nail to  grow its whole
length, varies from twelve to twenty weeks.
   522 a.  Basement  Membrane  of the  Skin.—The middle
layer  of the skin  is simply a basement  membrane, and  is in
fact the  mucous  layer  of the epidermis.   It is, however, of
little importance  in the functions of the skin,  and is believed
to be a separate layer merely because, when it  is immersed in
a solution of potash in  connection  with the  epidermis,  the
latter is dissolved, while the former is unchanged.
   523.   The  Corium;   its  Composition; Nerves  of  the
Corium.—The  Corium  or  internal  layer  is  the  true  skin,
since it possesses the vitality and sensibility of this membrane,
and contains all its vessels.   It is made up of white and yel-
low fibrous tissue, the white predominating, except  in  those
parts where occasional extension is required, where the yellow
exists in larger proportion.   The blood-vessels  of the corium
are very  abundant, terminating  in  the  minute  tubes which
supply the sudoriparous and sebaceous glands  : the proof of
the abundance  of which  we have in puncturing any part of

  Why do the nails sometimes grow after death?  Why do the nails seldom grow nat-
urally after an injury? At what portion are the nails the thickest ? 522 a. What is tha
middle layer of the skin ? 523.  Of what is the corium composed?  What is said of th«
abundance of blood-vessels in the corium? 
AND  PHYSIOLOGY.
299
the skin with the finest needle, when a drop of blood  is sure
to follow.   The nerves of  sensation too are very abundant, as
we know by the insertion  of a pin into any part of the body,
which invariably pains us, because we have wounded a nerve,
and not an expanded surface, like a membrane.

   524.  Sebaceous  or  Oil Glands.—The  Sebaceous  Glands
are small  elongated sacs which are  generally  gathered in
clusters about  each  of  the
hairs of  the body,  varying            FlG- 20°-
in number from four to twen-
tv.  They pour their  secre-
tion into the hair-canals near
their orifices,  and  are most
abundant in the parts  of  the
body most exposed,  as  in  the
skin of the nose.   Their se-
cretion in most places resem-
bles fat, although in the pas-
sage  of the external  car a
substance   resembling  wax
(cerumen) is poured out.
   524a.   Parasite  in   the
Sebaceous  Glands.—It  is a
fact curious,  if not  at  first
sight revolting, that there is
very constantly found in the
outlets to many of  the sebaceous glands a parasitic animal, as
represented by the  cut.  (Fig. 291,  p. 300.)   The occurrence
of this animal  in  almost every individual has led one anat-
omist to call it a " denizen" of the human body.

   525.  Sweat  Glands.—Length  of  Sweat Tube  in  the
Human Body.—The  Sudoriparous or  Sweat Glands essen'
 A  View of the Cerumen Gland
formed by the Contorted Tubes.  1, 1
The  Tubes.  2,  The Excretory  Duct.
3, The Vessels supplying it.
 What of the nerves in the corium ? 524. What are the sebaceous glands ? Where are
they the most abundant?  What is their secretion ? 524 a. What is said of the parasite
In the skin ? 
rjoo
HITCHCOCK'S  AXATOMT
Fig. 291.
   Psrasi*.«s of the Sebaceous Glands,  a. Two seen in their ordinary position at the
Or/_ce or ine _7and. b. Short Variety, c. Long Variety.

tially consist of long tubes convoluted and twisted upon them
selves, (Fig. 293, p. 301),  located just beneath  the corium
several of which  join to form an outlet,  which passes througl
the epidermis in a spiral manner, so that as it  opens exter
nally, a valve is made preventing the entrance of substance.
from without, but allowing a ready exit to all substances to be
discharged externally.   The size of the gland proper is about
^th of an inch in diameter, and that of the tube is about ^th
inch.  The outlets of these tubes (Fig. 292, p. 301,) are called
the pores  of the skin, and are somewhat larger than the diam-
eter of the  tubes.   The most remarkable fact, however, con-
nected with these glands, is their immense number in the sys-
tem.  Each tube when straightened measures  on an average one
fourth of  an inch in  length, and by actual count there are ; fc
least 2,800 in every square inch  of the  body.  (Fig.  293,
p. 301.)   Now the number of square inches in a man of or-
dinary height  is  2,500, which  would  make the number of
pores or  openings  about 7,000,000, or  the  whole  length of

  525. What is the general outline of the sweat glands?  What is their size ? now many
on every square inch of the body?  What is their aggregate length ? 
AND  PHYSIOLOGY
301
Fig. 292.
Fig. 298.
   Skin of the Palm showing Ridges, Fur-
 rows, Cross Groves, and Pores, or Orifices
 of Sweat Ducts.
 tube 145,853 feet, or 48,611
 yards,  or nearly  28  miles.
 Dalton says, 153,000 inches
 or two and a half miles.
   526.   The  Perspiration.
 —Sensible  and Insensible
 Perspiration.—The  secre-
 tion  poured  out   by  these
 glands, is a transparent liquid
 of an acid reaction, and of a
 saltish taste, commonly known
as sweat or perspiration.  This
is produced   in two forms,
known as sensible and insen-
sible perspiratibn,  which  is
escaping from  the  body  in
one  of these forms constantly during health, the sensible being
given off whenever excretion i3 so great  as to  leave  moisture
upon the skin.
            526. Describe the perspiration. What two forms ofit?
  Vertical Section of the Sole of the Foot
a.  Epidermis,  b. Papillary Structure.
c. Cutis,  d. Sweat Gland magnified forty
diameters. 
002
HITCHCOCK'S  ANATOMY
Fig. 294.
   527. Amount  of Watery  Vapor  Discharged  from  the
Body.—The amount of fluid which is lost from the body both
by the skin and lungs, is about eighteen grains  per  minute,
eleven by the skin and seven by the lungs.   This amount,
however,  varies exceedingly with  the  state of the health  and
the dryness  or  moisture of the  air,  Avhich, as already men-
tioned, regulates the temperature of the system.
   528.  The   Hair.—The hair is distributed over nearly every
portion of the human frame, and presents differences according
                                to age, sex, race,  or  individ-
                                ual peculiarities.   In length,
                                the hair  is  most  fully devel-
                                oped on the heads of females,
                                sometimes equaling the length
                                of the body,  while in male
                                beards it seldom reaches to
                                the waist.   The coarsest hair
                                is also found on women.
                                   529.  Size of   the  Hair-
                                Oil Glands.—In diameter the
                                hair   varies  from  Tioth  to
                                ao'ootb  of  an inch,  and  its
                                section  is  always of an oval
                                outline,  but  never  circular.
                                Nor is the  hair  of a uniform
                                diameter,  but it  is spindle-
                                shaped   almost  always,  and
                                terminates in a point.  At its
                                base  it  expands  into a  bulb
                                which is lodged  in  a sac in
                                295, p. 303. Just beneath the
A
,:'
  Sections of Human Hair, a, b, Trans-
verse  Sections showing the Cortical (or
external) and Medullary (or internal) Sur-
face,  c, d, Longitudinal Sections of Hair.
d, Shows the overlapping of the Epidermio
Scales of which hair is composed.

the true skin, as is seen in Fig.
epidermis one or more glands are situated which empty their
 527. What is the amount of watery fluid discharged from the body?  528. What is said
of the distribution of the hair? IIow long has the hair been known to grow?  52!).
What is tha diameter of the hair ?  What is the shape of it? What glands empty thei»
contents upon the bas« of each hair ? 
AND  PHYSIOLOGY.
303
contents into the same pore in
which  the hair itself  is lo-
cated.  This secretion is an oil
which  keeps  the  hair  in  a
smooth and moist state.
  530. Their Number.—The
number of the hairs  varies
with the color and portion of
the body.    In one  case  there
were found on  the  same sur-
face 147   black hairs,  162
brown, and 182 blonde.  On
a surface  one  fourth  of an
inch square the same author
found  on the scalp  293  hairs
and on the chin 39.
 Layer from Scalp, a, Oil Glands.  6,
Hair  c, Follicle.
   531.  Their   Distribution
and   Direction.—They  are
implanted  either singly or  in  twos or threes,  or even four
or five  together, and  their  direction is rarely perpendicular
to the skin, being, in a natural state, downwards.   They may,
however, be changed in their direction by persevering efforts,
as is sometimes seen by the brushing of the hair away from
the forehead.
   532.  Chemical  Composition—Durability.—They  differ
from most  tissues of the body by containing ten  per  cent, of
sulphur.   This, together with  the fact  that  they contain a
large per cent,  of nitrogen, accounts for the unpleasant odor
given off while burning.   They  resist decomposition better
than most  of the  tissues.   Those  of Egyptian  mummies  re-
main quite unchanged.  And it is owing to their durability
that they are used as relics of departed friends.
 530. What is said of the number of hairs on the body ? 531. How are they distributed,
and what direction do they take ?  532. How do they differ from most other tissues in
chemical composition?  How durable is hair? 
804            HITCHCOCK'S  AXATO)H
Fig. 296.
   533.  Constitution. —In
constitution the  hair  con-
sists of  three distinct  por-
tions,  an epidermis or outer
portion, a fibrous, and a med-
ullary portion.  The epider-
mis is arranged in the  form
of  ring-like  scales, whicl
overlap  each other  like the
shingles of a house, and is
about
rth of
an
inch
                                  thick (Fig. 294, d).   Hence
                                  we  see  the reason why  we
                                  can brush the hair  in  only
                                  one direction.   The fibrous
                                  portion  makes up  the prin-
  Highly Magnified Boot of Hair,  a, Shaft  cipal  bulk of  the  hair, and
 of Hair, b, c, Epidermic Sheath of Hair, d,  . r                      .
 Dermic, or External Sheath of Hair,  e, Epi-  IS Composed Ot  longitudinal
 dermic Scales.                        ceuS)  which  contain  paint
granules and air cavities which  give the  color to  the hair.
The medullary portion constitutes the central part of the hair
(usually from one third to one fifth its diameter), and  is made
up of cells varying  in diameter from ^oVo^h to  g oio ota 0I"an
inch in diameter.
   533 a. Color.—The color of the  hair  is thought by some
to be owing to the  iron contained in it, since it  is  said  that
there is  the most of this metal in the darkest hair.
  533 b.  Physical  Properties.—Hair  is  so  elastic that it
will  stretch without breaking  to  nearly one third more than
its original  length.    A single  hair of  the  head will suppoit
six  ounces  without breaking.   It readily  absorbs  moisture,
and  is dry and brittle or moist  and soft, according as the skin
or atmosphere is dry or  moist.    The beard  is  abundantly
 533. What three portions is each hair constituted of?  What makes the principal pan
Dfeach hair?  533 a. What is it possible that the color of the hair is owing to?  533 a
What is the strength of the hair ? 
AND  PHYSIOLOGY.
305
supplied with blond vessels, as
is seen by the cut.
  533 c. Rale of Growth.—
In  one  set  of experiment*
the hair has  been  found to
grow  seven lines  per  month.
Frequent   shaving    greatly
increases its growth.   It also
grows  faster  by day  than
by  night,  and   in   summer
than  in  winter.
                                  A small portion of the Follicle of a Hair
of the Beard, with the Arteries supplying it—very highly Magnified. 1, Its Follicle. 2,
Its Pulp.  3, The Trunk of the Hair without the Follicle.  4, 4, Two Arteries going
to the  Base of the Follicle.  5, 5, Their Distribution.  6, 6, The Reticulated Tissue of
the Follicle.

            FUNCTIONS   OF  THE  SKIN.

   534.  The  Skin a  Covering.—The skin is  the natural cov-
ering of the body of man, and he is not furnished  with any
further and more complete covering, as is the  case with many
of  the lower animals, since he is endowed with an  ability to
devise means of covering better suited to his condition than
one of hair, wool,  or  feathers.

   535.  Use of the  Epidermis—To  Protect  the  Nerves.—
The epidermis is of  use to protect the corium  and its vessels.
Without this covering many of our sensations acquired through
the skin Avould  be very painful.   The  contact of the softest
Eider down with the exposed nervous filaments would impart
tiie acutest pain, and the rays  of the noonday sun would in-
flict  the keenest  torture.   The body  could  not endure the
 ightest  clothing, and even our motion  through the  air would

  533 c What is said of the rate of growth of the hair ?  534. What is said of the skin as
a covering ? 535. What is said of the epidermis as a source of protection to the delicate
nerves of touch ?
Fig. 297.
 
306
HITCHCOCK'S  ANATOMY
be a source of misery.   But these delicate  nerves are pro-
tected by an insensible membrane, which, though hard, elas-
tic, and a very perfect guard of these  faithful  sentinels, per-
mits all the necessary impressions to pass through them.  The
epidermis also guards the most delicate parts in a careful man-
ner, by thickening its substance over the ends of the fingers,
and in all places where sensation is  most  acute.   It  is also
speedily renewed where friction or accident removes it, as  on
the palms of the hands and soles of the feet.
   536. To  prevent  Absorption.—Another important use of
the epidermis is to prevent undue absorption.   For the lym-
phatics only penetrate the corium, and cease at the under sur-
face of the epidermis.   Consequently but very  little fluid can
enter these vessels unless the epidermis  is removed or satu-
rated with fluid   Were it not for this protection, almost every
liquid substance brought in contact  with the surface of the
body  would at once be introduced into the general circulation,
thus exposing the system to serious danger by absorbing poi-
sonous matter.
   537. To  Prevent Excessive   Perspiration—Danger from
an opposite direction is also warded off by the impenetrability
of the epidermis.  Were it not for the tortuous direction which
the outlets of the sweat glands take as they empty themselves
upon  the surface of the  body, an excessive amount  of water
would be set free,  and thus greatly reduce  the  system.  But
owing to this arrangement of sweat ducts, it is only when the
system is very much stimulated that any considerable amount
of water can be discharged by sweating.   Were not this the
case, the body would often be reduced to a low state  from the
loss of the watery portion of the blood, as is  sometimes seen
in excessive sweating.
  538. Use of the  Corium —Contains the  Blood-Vessels
 536. What is the use of the epidermis to prevent undue absorption ?  537. How does
the epidermis prevent undue perspiration ?  What harm would result from excessive
sweating ? 
A X D  PHYSIOLOGY.
n a""
and  Nerves—Amount  of  Waste Escaping from the  Skin.
—In the corium, or internal layer of the skin,  resides the vi-
tality.   Here the arteries terminate in the capillaries and the
nerves double upon themselves, producing  the  highest  sensi-
bility to external impressions.   So that when any function of
the skin is spoken of, reference is usually made to this inner
layer.   And we see that the skin is not only useful as a pro-
tection and covering to the body, but is of great  value  as an
excretory  apparatus.   And  in  this  office the skin is pecu-
liarly  valuable, since  it removes  a  great amount of matter
from the  system that the lungs cannot  remove.   The  actual
amount of waste matter escaping daily from the skin is given
variously  by different writers.  All, however, make  out an
average of from thirty to forty ounces,  or if condensed  to
water, about two pints.  A proof that the vapor of water es-
capes in the form of insensible perspiration is had by placing
the  dry hand upon a cold glas3 or polished metallic substance,
when moisture in a few seconds condenses on the surface.
   539. Uses of  the  Oil  Glands—Renders  the  Hair  Soft
— Softens  the  Skin — Protects  the   Eye —Guards  the
Membrana Tympani.—The function of the sebaceous, or oil
glands of the skin seems to be the secretion of substances  pro-
tective to the skin.   These are  mainly oily products, and are
 given  off at the roots of the  hair, so as to give it flexibility,
 that by its stiffness it may not irritate the skin.   The oil tubes
are  most  abundant on those parts of the body which are most
exposed,  and especially the face and neck.  The design of the
secretion seems, to be to give flexibility to the skin, to prevent
the  heat and air from drying it so that it would crack in man/
 plrees, and also to lubricate it when  brought into contact  with,
 foreign substances, as is the case so frequently with the hands
 The oil of the skin also prevents moisture from adhering to it,
and thus  its functions  can  be more  perfectly carried on, and
  53S. Where lies the vitality of the skin ?  What other use than a protection is tha
skin? Hrw  much waste matter escapes daily from  the skin ?  How many pints? 539.
What is the use of the oil glands? How does it affect the  hair? What value does it
Impart to the skin ? 
308            HITCHCOCK'S  A X A T O M V

it will noi, eetain all dust which chances to fall upon it.   At
the flexions cf the joints, and all those places where two sur-
faces of the skin are frequently brought in  contact, this oily
secretion is abundantly poured out, in order that there may
be as  little friction as possible between the opposing surfaces.
Upon the edges of the eyelids is situated a row of glands which
pour out their secretion in such a manner as to retain the tears
—the  lubricating fluid of the eye—when produced  in their
ordinary quantity ; but when in excess, as  in weeping, they
run over their boundaries, and flow down the cheek. The use
of these glands may be  well appreciated in some diseases  of
the eye, where the tears constantly run down upon  the cheek,
producing irritating sores.
  In the  passages of the ears we find the same glands,  al-
though their secretion is of a somewhat  different  character.
Here  it  is a clammy, viscid substance, of a yellowish  color,
and from its appearance it is called the wax of  the ear.   Its
service is to prevent dust and foeign substances generally
from  gaining access to  the internal ear, where they would
injure  the sense of hearing.
               HYGIENIC   INFERENCES.

  540.—1. Great  Value  of this  Membrane  in  the  Ani-
mal Economy.—From the complicated structure of the skin,
we see that this membrane is of  great  service in the  animal
economy.   It stands next  in importance  to the lungs as  an
excretory organ, and if its  functions are interrupted the whole
system very soon feels the disturbance.
  541.— 2. Its Health Requires  Cleanliness.—The  skin
must be kept clean to secure the  proper functions of the  per-
spiratory glands.   This  not only implies the necessity of fre-

  How does it affect the skin at the joints? Of what service is it  to the eye? Of what
to the ear ? 540. State the relative value of the skin in the animal economy.  541. Why
U cleanliness essential for the health of the skin ? 
AND PHYSIOLOGY.
309
quently washing the whole surface of the skin, but  also the
frequent change of the bed-clothes, under-clothes, etc.  And
it should be a fixed rule with  every  one to change the  linen
and  under-garments  both  night  and morning ; that is, the
under-garment worn  during the  day should  not  be  worn  at
night, and the reverse.

  542.—3.  Must  be Kept  at a  Uniform Temperature.^
f'e also learn that the skin should be kept at a uniform tem-
perature, and up to its normal standard.   It  therefore needs
proper clothing,  not so much in the coldest weather—for then
our feelings will impel us to do it—but at the changes of tem-
perature so common and so  great in our climate in spring and
autumn, for then we are too apt to neglect it because we feel
no especial  inconvenience,  and  yet  at  these times  there  is
more danger of disease from a want  of  proper clothing than
at any other season of the year.   We seldom  injure ourselves
by too much clothing, because we can easily throw of superflu-
ous garments, but often do it by  too small an amount of pro-
tection.  An  important rule for every  one  is, when going
abroad even a short  distance  from home,  to carry  with him
an over garment when exposed to evening air.
  543.-4. Must  Come  in  Contact  with  the  Air.—The
skin imbibes  oxygen from the air, and hence it is importa.
that air be brought in contact  with this membrane.  Th_
clothing should be worn so loosely that a thin layer of air will
be in contact with nearly every part  of the skin.
  544.—5. Needs Friction.—Frequent  and thorough dry
friction applied to every part  of the skin greatly promotes the
health,  not only of this membrane, but of the whole body.  So
smooth  are the clothes we generally wear  next the skin, that
but little stimulus is received  by them, and hence a thorough
 542. What is necessary for the temperature of the skin, especially for changes in
weather? What is said of an over-coat as a constant traveling companion ?  543. Why
shonld the skin have air in contact with it ?  544. What is the use of frictioo to the
fckin? 
310
II I T C II C O C K ' S  A X A T 0 M Y
rubbing of the whole body every night and morning will aid
greatly in this matter.
  545._6. Injurious Effects of Moisture upon the Skin.
.—Moisture if applied to the skin for a considerable length of
time interrupts its  functions, and accordingly we infer that
wet or damp  clothing should not be allowed to remain on the
body any longer  than is  absolutely necessary.  If, however,
dry clothing  cannot be procured immediately, the body should
be kept in vigorous action of  some kind until  the clothes can
be changed.   This inference is of equal  application, whether
the whole of  the body be wet, or only a  portion of it, as the
feet.
  546._7.  Service  of a Daily  Cold  Water  Bath.—We in-
fer again that a daily cold water  bath  is  of great  service for
all  students  and sedentary persons who  are  in health.  Not
only is it desirable on account of cleanliness, but a serviceable
shock  is  thus imparted to the nervous system.  It, however,
should be  taken as  speedily as possible, the  essential thing
desired being, that   pure water  should  be spread  over the
whole  surface of the body,  and after  it  that  the skin should
be speedily and vigorously wiped dry.   The secondary effect,
however, the stimulus imparted  to the nervous system by the
shock, is by  no means an unimportant issue to be gained.
          COMPARATIVE  DERMATOLOGY.

   547. Covering of Mammals.—The skin of mammals very
closely resembles that of man, with the exception of the epi-
dermis and its horny appendages, which are usually covered by
hair.  The fat tissue, too, just beneath the skin, is often develop-
ed in a surprising degree, and the corium in many instances is
very thick.   Some  have horny scales,  and others  long plates.

 545. What are the injurious effocts of too much moisture applied to the skin? 546,
What is said of a daily bath, and what  regulations concerning it?  547. What is said ol
the covering of mammals? 
AND  PHYSIOLOGY.
311
   548. Callosities.—In many of the rodent or gnawing ani-
mals, the carnivora and camels, the epidermis about the joints
becomes very thick, making callosities or  pads for  the sup-
port and protection of the parts exposed.
   549. Epidermic Scales.—True EpidermicScales are found
on the tails of many animals, such as the Beaver.
   550.  Horn of  Rhinoceros.—The so-called  horn  of tho
Rhinoceros is nothing but a thickening of the epidermis until
is assumes the form of a hollow cone.
   551.  Varieties of   Hair.—The  hairs  upon the external
surface of mammals either  present  no greater  irregularities

            Fig. 298.                      Fig. 299.
         Hair of Sable                    Hair of Musk Deer.

than do those of man, or  they are slightly  rough, like  those
of the Squirrel,  or knotty, as in the Bear, or furnished with
pointed processes, like  the teeth of a saw, in other animals.
Some  of  these  peculiarities  are exhibited  in the  adjoining
cuts.   The spines of the Porcupine and Hedgehog differ from
hairs only that they contain the same materials  in a more con-
densed form.
  552. Glands   of  the  Skin. — Cutaneous  and sebaceous
glands are present in  most mammals very abundantly.  The
 548. To which membrane of the skin do the callosities of camels, etc., belong?  549.
Where are epidermic scales found ? 550. What is the horn of the rhinoceros ?  551. What
are the varieties of hair in different animals?  652. What is said of glands of the skin
 
312
HITCHCOCK'S  A X A T O il V
Fig. 300.                       Fig. 301.
\. B. Hairs of Squirrel. C. Hair of Indian Bat.
 latter secrete an unctious fluid, which  is usually of a strong
 smell.
   553.  Skin of Birds.—The Skin of Birds is thin and desti-
 tute of cutaneous glands, except one at the tail, which is gen-
 erally present.   The whole body is covered by feathers, except
 certain parts of the head, legs, and feet.  There it becomes very
 much  thickened, forming callosities, wattles and  combs,  in
 which, beside the cellular tissue, are found the elastic and erec-
 tile tissues, as well as red and blue  tells of coloring  matter.
 Upon the toes and feet are found plates and scales of horny tissue.
   554.  Feathers  of  Birds.—The  Feathers  of Birds   are
 made up of the Quill and Vane: the  former giving  it attach-
 ment to the body, and  the latter forming its expanded surface.
 The Vane is made up of a small number of laminse  or plates,
 which both form a  light  and firmly resisting medium to  the
 air, and serve to retain the heat within the body.   When per-
 fectly formed the laminse are furnished with a hooklet at their
 free extremities, by which  they are  attached to  each other,

 553. What is the thickness of the skin of birds compared with that of mammals?
What are the wattles and combs?  554. What two parts are feathers made up of?  Why
are the lamina; furnished with a barb at each extremity? What is the design of their
overlapping each other ? 
AND  PHYSIOLOGY.
313
thus  making each  feather  an  impenetrable plana,  surface.
The feathers also overlrp one another  to a  considerable de-
gree, and as they thus contain air, and are  themselves non-
conductors, they afford the most perfect  protection to the body
against the cold.
   555. Skin  of  Amphibia.—The naked Amphibia, such  as
the Froo-s, have a smooth slippery skin, which is continually
 Liing cast off in patches  or shreds.  This skin surrounds the
solid parts of the body very loosely, and spaces for lymphatic
 vessels are found beneath.  It is  always composed of several
 layers of fibres which lie at right  angles with each other.
   556. Scales  of  Serpents.—Upon some serpents, scales are
 found which overlap one  another, like the shingles of a house,
 as is also the case with fishes.   Scales  with  tubercular spines
 are met with on some reptiles, and in some instances, as those
 of  Crocodiles  and  Tortoises,  they contain  bony matter, and
 coalesce with the bones of the skeleton.
   557. Exuviation of   Serpents.—Many Serpents cast their
 Bkin several times during the year, either by piecemeal, or  by
 drawing off  the whole at once.  One species of Tortoise d^es
 the same thing, as well as several Lizards.   This  is an anal-
 ogous function to the moulting  of birds, and shedding of the
 coat in mammals.   This generally takes  place in  Spring,
 but frequently  upon a change of weather several times in the
 year.  At  each period,  when this  is  effected by the Rattle-
 Snake, a new segment is said to  be added  to the tail, which
 seems quite  probable, since  the  rattle  is merely a  condensed
 portion of the epidermis.
   558.  Scales of  Fishes.—Classification  of Fishes   by
 1  eir Scales.—Fishes have an Epidermis which is  sometimes
 covered with scales, and  sometimes  not, though always lubri-
 cated most  thoroughly by a copious mucous secretion.  The

  555. What is said of the skin of frogs? 51f>. Do serpents ever have scales? 557. What
 is the exuviation of serpents? When does this take place?   What peculiarity in t_«
 rattle-snake ? 55S. IIow are tho scales of fishes arranged ? 
:u4
II I T C II C 0 C K ' S  A N A 1  O M Y
Bcales are sometimes disposed in an imbricated manner upon
the body, and are not situated in the epidermis, "but really
in the skin, and  included  by it."   The  scales contain both
phosphate and carbonate of lime as a rule.  Their shapes are
various,  though Professor Agassiz, the  best living  authority
on fishes, has grouped all  bony fishes under four orders, de-
pendent  mainly upon the form of the scale.   First, the Pla-
coidians, including such  fishes as the Sharks and Rays, where
the scales are  either large  and covered with  bony tubercles,
or simply with  small enameled  scales.    Second, the Ganoi-
dians,  including the Sturgeon and bony Pike, which have
angular  bony plates coated  with a thick  layer of enamel.
Third, the  Ctenoidians,  such as the Perch,  which have hard
scales jagged  on  the outer edges,  like  the teeth of a comb.
Fourth,  Cycloidians. These have soft and circular scales with
simple margins. In this order are found the  Herring and Sal-
mon.   Sometimes the scales are provi 'ed  with a  hook-like
process,  which  overlaps  and fastens itself into a depression in
the scale beneath.
   559.   Tegument  of  Articulata.—Horny  Case  of  In-
sscts.—The Tegumentary envelop of the sub-kingdom Arti-
culata  has already been described  under Comparative Oste-
ology, since the skin of many of this sub-kingdom, especially
the Crustacea and insects, is in reality the only skeleton these
anim.ils have.    Insects have a covering  sometimes  leathery
and  soft, and  sometimes horny  and solid,  which contains a
peculiar  proximate (chemical) principle known as Chitine.
   560.   Mantle  of   Molluscs. — In  Molluscous  animals,  a
dermis, which  is  a  muscular  skin, envelops all the viscera,
and hence is called  the  cloak or mantle, which secretes tli3
hard calcareous covering known as  the shell.   Generally the
shell is external to  the  mantle,  as  in the Clam and Oyster,

 What are the four orders dependent upon the form of the scale? Who is the author
of this arrangement ?  Give examples of each.  559. What is the covering of the articu-
lata' What is peculiar about its chemical composition ?  560. Describe the outside cov-
ering of molluscs. 
AND  PHYSIOLOGY.
315
but  often,  as in the Cypraea  or Cowry,  the mantle extends
over the shell.

   561.  Radiates.—With the  exception of the hard  external
skeleton of these animals already described, their proper  skin
is mostly thin and  soft, allowing  of great flexibility and some-
times of great expansion and contraction.
   The  Protozoa have  a very delicate, cutaneous envelope,
sometimes  smooth and sometimes covered with cilia.

  Effect of Fright on Hair.—A Sepoy of the Bengal Army,  brought as a
prisoner for examination  before the British  officers, was terribly  affrighted,
trembled like a leaf, and was almost stupified with fear.   Such was the shock
upon his brain that his hair, from a glossy jet black, became gray within the
space of an hour, the subject being only  twenty-four years of age.
  Also a boy, let down from a high cliff on the coast of  Scotland to get eggs
of sea-birds.  He, in defending himself from the birds with the sword, struck
the rope  by which he was  suspended, and cut off every strand but one.
When drawn up his hair was white.
  Maria Antoinette experienced a change in the color of her hair during one
night's excessive fear. 
         CHAPTER   SEVENTH.

THE INSTRUMENTS  OF  ANIMATION.—NEUROLOGY, OR
             THE BRAIN AND NERVES.
        DEFINITIONS   AND  DESCRIPTIONS.

  562.  Main  Features  of  the  Nervous  System.—We
now come to an  organization which  is very complicated in
structure,  some  of whose functions  are the most obscure of
any in the body.   It is called the Nervous  System :  and the
different  grades in the animal  kingdom  are established  by
placing those  having the  most  complicated nervous  system
highest on the scale.  Man  having the largest brain in pro-
portion to the rest of his  body, and  possessed of the greatest
relative amount of nerves, is therefore placed at the  head of
the animal kingdom.
  563.  Microscopic Structure.—Tubular  Portion.—Diam-
eter of the  Tubes.—In  microscopic structure  the  nervous
tissue presents two essential elements: the fibrous or  tubular,
which is mainly found in the nerve trunks, and the cellular or
vesicular, existing more abundantly in  the  ganglia or nerve
centers. In the former the tubes  are the largest in the trunks
of the nerves, and gradually diminish as they  approach  the
brain, varying in size from  the 27'ooth  to the ?t o-ooth of an
inch, and sometimes existing even as large  as the s^th of an
inch.  They are sometimes  conical also, measuring at one end
from T_'ooth of an  inch  to oinooth: the smallest end  being
found near the nerve trunks, and are sometimes called coarse
  562. Give the leading features of the nervous system.  563.  What are Uie two micro-
wopic elements of nervous tissue ? Give the size of the tubular portion. 
AND  PHYSIOLOGY.              317
Fig. 302.
Tubular Nerve Fibers.
nerve fibers. These fibers have the appearance of a double tube,
or a small tube within a larger one, and sometimes exhibit small
nucleated cells within the two.
   564. A closer examination shows an inner or grayish por-
tion which is called the axis cylinder, and  a white substance
around this called  the medullary  matter, or substance  of
Schwan, and outside of the whole a membranous tube.  (Fig.
302.)   They are often called Fine Nerve Fibers.   The sym-
pathetic system,  on the other hand, seems  to be made up  of
tubes  without this double structure, and when  several  of
them  are joined  in a  bundle, they present a grayish appear-
ance.    They are also of a  much smaller size, varying mostly
from rjdooth to  T„Voth of an inch.
   565. Vesicular  Structure.— The vesicular substance  is
composed of cells or  vesicles,  which  present very  curious
forms, being somewhat stellate or caudate.   The central por-
tion is  globular, consisting of a nucleated  cell, which sends
off processes  in  different  directions,  as seen in the  annexed
Figure  303.  Their diameter is exceedingly variable, meas-

 What is the structure of the sympathetic system ?  564. What still more minute struc
ture can be detected by the microscope ? 565. Describe the vesicular structure.  Giva
the diameter of the cells. 
318             HITCHCOCK'S  ANATOMY

                           Fig. 303.
  Vesicular Nerve Corpuscles,  a. Cell Wall.  b. Cell Contents,  c. Pigment,  d. Nu.
cleus. e. Prolongation forming Sheath of the fiber. /. Nerve Fiber, magnified 35D diam-
eter.

uring from ? J-^th to jAoth of an  inch.   These are found in
the ganglia and the substance of the brain.
   566.  Divisions  of  the  Nervous  System.—The  nervous
system consists of a central portion contained  within the cav-
ity of  the skull and  the spinal  column, and a great  number
of white threads  ramifying through every part of the body.
The physical condition upon which the  activity of the ner-
vous system depends, is the supply of arterial blood.
   567. Cerebrum.—If we examine the parts within the skull,
(Fig. 304,  p. 319,)  we shall find the greater mass of it to be
of a spheroidal form, divided nearly into two halves by a deep
fissure  or  cleft, and its  surface is  singularly  roughened  by
elevations and depressions called anfractuosities.
   568. This  mass is the Cerebrum or Great Brain, and the
two divisions are called its  hemispheres.  (Fig. 307, p. 321  )
   569. In man the average weight  of the brain is fifty-four
ounces, in females forty-five; the maximum being sixty-four,
  566. Wh:it principal divisions does the nervous system consist of? 667. Describe the
cerebrum.  569. What is the average weight of the brain? 
AND   PHYSIOLOGY.
319
                 Fig. 301.
a           f      h                    c
  Vertical Section of the Brain,   Cerebellum, Pons Varolii, and  Medulla Oblongata,
 a, Anterior Lobe of the Brain, b, Middle Lobe, c, Posterior Lobe, d. Cerebellum, e, Me-
 dulla Spinalis, f, Section of the Corpus Callosum.  The Lateral Ventricles of the Brain
 are situated on either side of the Corpus Callosum, which assists in forming their Upper
 Wall.   g. Optic Lobes :   1,  Olfactory Nerves.  2, The Eyeball, from which may  bo
 traced the Optic  Nerve as far as the Optic Thalami or Lobes.  Close to this is the Nerve
 of the Third Pair.  4, The Fourth Pair, distributed, like the Third, to the Muscles of the
 Eyes.   5, Superior Maxillary Branch of the Fifth  Pair.  5', Ophthalmic Branch of tho
 same Pair of Nerves. 5",  Inferior Maxillary Branch of the same Pair of Nerves. 6, Sixth
 Pair, proceeding to the Abducentes Muscle.  7, Facial Nerve:—under the origin of this
 nerve may be seen a portion of the Acoustic  9, Nerve called Glosso-Pharyngeal.  10,
 Pneumogastric Nerve ; close to it is 12, the Spinal  Accessory.  These three Nerves, the
 Glosso-Pharyngeal, Pneumogastric, and Spinal Accessory, are by some reckoned as one
 pair. 11, The Ninth Pair of some, and the Eleventh of others, called also Hypoglossal.
 14 and 15, Cervical  Nerves.


 and the  minimum twenty;  the  average  capacity of the cra-

 nia  of Germans and Anglo-Saxons is  ninety  cubic inches.

 Daniel Webster's cranium contained 122 cubic inches.

   570.  Cerebellum.—The Cerebrum, by  a  band  of thick

 fibers, is  connected with another  body, of  a pear  shape,  at-

tached  to it  by its base, called the  Lesser Brain or Cerebel-

lum.     (Fig. 306,  p.  320.)    This has about one  eighth of the

  State  the average  capacity of Anglo-Saxon crania, and also that of Daniel Webster,
570. Describe the cerebellum.
H* 
320
HITCHCOCK'S   ANATOMY
weight  of the Cerebrum,  and lies  directly  behind  and  be-
peath  it.
                  FiG. 305.                      The Lateral  Ventricles  of  the
                                               Cerebrum.  1, 1, The two  Hemi-
                                               spheres cut down to a level with
                                               the  Corpus  Callosum,  so as  to
                                               show the  Centrum  Ovale  Majus.
                                               The Surface is  studded  with  tho
                                               small  Puncta  Vasculosn.   2,  A
                                               small portion of the Anterior Ex-
                                               tremity of the  Corpus  Callosum.
                                               3, Its Posterior  Boundary;  the in-
                                               termediate portion, forming the
  Iss,   h   i; lw/l Y\!(  'i'  '''7  (~~S    Pwoof of the Lateral Ventricles, has
   v~^_  >  ',',  £llMiJt $\\i't,. \mk '   \'  -v   ^1    been removed so as to completely
                                               expose these Cavities.  4, A part
                                               of tho  Septum Lucidum, showing
                                               a space between its Layers which
                                               ii the Fifth Ventricle. 5, The An-
                                               terior Cornu of one Side.  6, The
                                               commencement of the  Middle
                                               Cornu. 7, The Posterior Cornu.
                                               F, The Corpus  Striatum of one
                                               Ventricle.  9, The Trenia Striata.
                                               10, A small part of the Thalamus
                                               Opticus.   11,  The  Plexus Clio-*
                                               roides.  12, The Fornix. 13, The
                                               commencement of the Hippocam-
pi Major in  the  Middle Cornu.  The P.ounded Oblong Body in the Posterior Cornu
01  lie Lateral Ventricle, directly behind the Figure 13, is the Hippocampus Minor.  A
P»«3tle is seen In the Foramen of Munro.
Fig. 306.
  A View of the Interior Surface of the Cerebellum and a Portion of the Medulla Ob-
longata. 1, 1, The Circumference of the Cerebellum.  2, 2, The two Hemispheres of the
Cerebellum.   3, Lobulus Amygdaloides.  4,  The Vermis Inferior.  5, Lobulus Nervi
Pneumogastriei.  6, The Calamus Scriptorins.  7, Its Point.  8, Section of the Medulla
Oblongata.  9, Points to the Origin of the Pneumogastric Nerve. 
                      AND   PHYSIOLOGY.                    321

   571.   Cerebral  Ganglia.—Also  lying directly  upon  the
base of the brain, are  found several  distinct enlargements  or

                                  Fig. 307.
  A View of the Base  of the Cerebrum and Cerebellum, together with their  Nerves.
1, Anterior Extremity of the Fissure of the Hemispheres of the Brain.  2, Posterior Ex-
tremity of the same Fissure.  3, The Anterior  Lobes of the  Cerebrum.  4, Its Middle
Lobe.  5,  The Fissure  of Sylvius.  6, The  Posterior Lobe of the  Cerebrum.  7, The
Point of the Infundibulum.  8, Its  Body.  9, The  Corpora Albicantia.  10, Cineritius
Matter.   11, The Crura Cerebri.  12, The Pons Varolii. 13, The Top of  the Medulla
Oblongata.  14,  Posterior Prolongation of the Pons Varolii.  15,  Middle of  the Cerebel-
lum.  10, Anterior Part of the Cerebellum.  17, Its Posterior Part and the Fissure of its
Hemispheres.  IS, Superior Part of the Medulla Spinalis.  19,  Middle  Fissure of t! 3
Medulla Oblongata.   20, The Corpus Pyramidale.  21, The Corpus Restiforme.  22, Tl a
Corpus Olivare.  23,  The Olfactory Nerve.  24, Its  Bulb.  25, Its External Root.  2",
Its  Middle Root.  27,  Its  Internal  Root.  28, The  Optic Nerve beyond the Chiasm.
29, The Optic Nerve before the Chiasm.  30, The Motor Oculi, or Third Pair of Nerves.
31, The Fourth  Pair, or Pathetic  Nerves.  32, The  Fifth  Pair, or Trigeminus Nerves.
83, The Sixth Pair, or Motor Externus.  34. The Facial Nerve.  35, The Auditory—the
two making the  Seventh Pair.  36, 37,  38, Tho Eighth Pair of Nerves.  (The Ninth Pair
are not here seen.)
571. What are the cerebral ganglia? 
322
HITCHCOCK'S  ANATOMY
FlG.  308.
ganglia, tho most  important of which are  the Thalami Optici,

Corpora Striata, Olfactive Ganglia, and Tubercula Quadrige-

mina.

                                572. Spinal  Cord.—Upon the an-

                              terior   portion  of  the  Cerebellum,

                              commences the  Spinal Cord, the up-

                              per portion of which,  situated within

                              the skull,  is  about  three inches in

                              length  and  one in breadth,  and  is

                              called  the Medulla Oblongata.

                                573.   Cerebro-Spinal  Center__

                              Thesj  portions  of  the nervous  sys-

                              tem constitute what is known  as the

                              Cerebro-Spinal  Axis  or Center, and

                              are all made up of two kinds of mat-

           W^t--
                               The Cerebro-Spinal Avis seen  Anteriorly. The
                              Nerves have  been cut through at a short distance
                              from their Origin or central termination,   a. The
                              Cerebrum, b, Anterior Lobe of the Left Hemisphere
                              of the Brain,  c, Middle Lobe,  d, Posterior Lobe, al-
                              most concealed by the Cerebellum,  c,  The Cerebel-
                              lum. / The Medulla Oblongata or Bulb. 1, First, or
                              Olfactory Pair of Nerves.  2, Second Pair, or Optic.
                              3, Third Pair, or Motores Oculorum.  4, Fourth Pair,
                              or Pathetic.   5, The Facial, or Fifth Pair.  6, Sixth
                              Pair, or Abducentes.  7, Nerves of the Seventh Pair,
                              or Facial;  also the Acouslic,  or  Portio Mollis,  by
                              some called the Auditory, and  viewed  as a  division
                              of the Seventh ; others call them the  Eighth Pair.
                              9, The Glosso-Pharyngeal Nerves, called the Ninth
                              Pair by some, by others the Anterior Division of the
                              Eighth Pair.  10, The Pneumogastric, by some  in-
                              cluded in the Eighth Pair, by others called the Tenth
                              Pair.  11, Nerves of the Eleventh and Twelfth Pairs,
                              tho first beinsr viewed by some as a Division of the
                              Eighth Pair, and called Spinal  Accessory; the latter,
                              called by some the Ninth, by  others the Twelfth, is
 :_e Motor Nerve of the Toigne. 13, Nerves of the Thirteenth Pair, or  Sub-Occipital. 14,
 15, 16, The First, Second, and Third Pairs of Cervical Nerves, g, Cervical  Nerves form-
 ing the Brachial Plexus.  25,  One of the Pairs of Nerves of the Dorsal Portion of tli■<
 Spinal Marrow. 33,  One of the Pairs of Lumbar Nerves,  h.  Lumbar  and Sacral Nervca
 forming the Plexus whence come the Nerves of the Lower Extremities,  i and j, Ter
 mination of the Spinal Marrow, called Cauda Equina, k, Great Sciatic Nerve proceed.
 ing to the Lower Extremities.

   572.  What is the medulla oblongata? 573. What two kinds of matter does a slicing oi
 the brain show, and how is the gray and white matter disposed ?
 
ANO  PHYSIOLOGY
Fig. 309.
ter; the gray or external, and the white  or internal.   This
structure is best seen when the brain is cut through in a hori-
zontal direction; the gray showing itself  as an outside layer
with an irregularly scolloped edge, while the white is internal,
and constitutes the greater portion of the whole brain.
   574.  Blood-Vessels  of  the  Brain—Venous   Si;^usesi
—The blood-vessels of the brain are very numerous, since one
sixth of all the blood is sent to this organ, although its weight
is about one  fortieth of the body.  The arteries are the most
numerous, and as already mentioned, those entering  the head
from the front side of the neck, communicate very freely with
those coming in at the back side of the head, (see Fig.  213),
making a perfect circle of  communication, so that there may
be no impediment to the cir-
culation of the blood through
the nervous center.  The veins
are not numerous.  Some are
found  on  the surface  of the
brain,  but only  a few pene-
trate into its substance.   But
large channels are found  be-
tween  the membranes called
Sinuses, which  do  not  pre-
sent the ordinary characteris-
tics of veins,  except  that they
convey  the blood to the heart.
The two sinuses which are of
the  largest   size,   discharge
their contents into the jugu-
l  r veins.   (Fig. 309.)
  575.  31 em branes  of the
Ccrebro Spinal  Center.—
Dura Mater.—Three  mem-
  Sinuses of the Base of the Skull. 1, Oph-
thalmic Veins.  2, Cavernous Sinus. 3,
Circular. 4, 6, Inferior Petrosal. 5, 9, Oc-
cipital Sinuses. 7, Internal Jugular Vein.
 574. What proportion of the blood goes to the brain?  Which are the most numerous
thw arteries or the veins ? What are the sinuses found there ? 
324
HITCHCOCK'S  ANATOMY
         branes envelop the brain, although to the unassisted eye they
         appear as one.   They are of great importance in the economy
         of  the brain, and are often  the seat of severe disease.   The
         outer  one is called  the Dura  Mater,  that  covers both the
         brain  and spinal cord,   and is  attached firmly to the bones
         which it covers.   It has the same composition as  the liga-
         ments of the body—white fibrous tissue—and consequently h
         very tough,  being the firmest of the three membranes.
           576.  Arachnoid  Membrane.—The  Arachnoid Membrane
         lies directly beneath the dura  mater, and receives  its name
         from the Greek word signifying spider's web.
           577.  Pia   Mater.—Closely beneath  it  is  the  Pia  Mater,
         which lies directly upon the  surfaca of the  brain,  and  dips
         into all the  cavities or convolutions  on its surface.   This
         membrane is especially  serviceable in the  nourishment of the
         brain, and receives  the   arteries which  enter at the  anterior
         and posterior part of the skull.    Its nerves are branches of
         the sympathetic  system.
           578.  Surface  of  the  Brain.—The surface of the brain is
         very  uneven, being  covered with  convolutions  or tortuous
         ridges and corresponding depressions, the  design of which  is
         not as yet well known,  though  probably merely to procure a
         greater amount of surface, and  they do  not correspond  to the
         irregularities on  tho surface of the skull from which phre-
         nologists profess to judge of character.
           579.  Ventricles  of  the  Brain.—Within the brain are sev-
         eral cavities called ventricles, of which the special use has not
         been determined.  (Fig. 305, p. 320.)  It is a curious  fact,
         however, that a post mortem examination  of  the  brain of in-
         ebriates frequently discovers these cavities to  be partially filled
         with alcohol.
           580. Division of  the Nerves.—All the  nerves  that  pro-
i
          575. How many membranes enveloping the brain ?  Describe the dura mater. 576.
!         Describe the arachnoid membrane. 577. Describe the pia mater.  What are its nerves?
         578. What is the condition of the surface of the brain ?  579. What are the cavities in th«
         brain called ?  580. How are all the nerves given off from the brain and spinal cord ? 
AND   PHYSIOLOGY.
325
ceed  from the cerebro-spinal axis  are  given off in pairs  on
opposite sides of  the median line of the body.   They are  di-
vided into two sets ;  those which are given off from the great
brain, little brain, and medulla oblongata, being called cranial
nerves,  and those from the spinal cord, spinal nerves.
   581.  Cranial  Nerves.—Many of the cranial nerves, and
all of the spinal  nerves, arise by two roots, and  soon  form a
small protuberance, which  is called  a Ganglion or knot, in
which the  fibers are confusedly mixed  together, after which
they proceed  in the same sheath to  their destination.
   582.  Of the cranial  nerves there  are twelve pairs,  named
as follows :
First pair.
Second "  .
Third  "  .,
Fourth "  .
Fifth   "  .
Sixth  "  .
. Olfactory.
.Optic.
.Motores Oculorum.
.Trochleares.
.Trifacial.
. Abducentes.
Seventh pair. .Facial.
Eighth   "  ..Auditory.
Ninth    "  . .Glosso-Pharyngeal.
Tenth    "  .. Par Vagi.
Eleventh "  . .Spinal Accessory.
Twelfth   "  .. Lingual.
583.  Olfactory.—The  ofactory nerves arise from the an.
Fig. 310.
  A View of the First Pair, or Olfactory, with the Nasal Branches of the Fifth. 1, Frorc.
tal Sinus. 2, Sphenoidal Sinus. 3,  Hard Palate.  4, Bulb of the Olfactory Nerve. \
Branches of the Olfactory on the Superior and Middle Turbinated Bones.  6, Spheno-
palatine Nerves from the Second of the Fifth.  7, Internal Nasal Nerve from the First
of the Fifth. 8, Branches of Seven,  to Schneiderian Membrane.  9, Ganglion of Cloquet
in the foramen incixivium. 10, Anastomosis on the Inferior Turbinated Bone of tha
Branches of the Fifth Pair.
  What are the two principal groups of nerves? 581. How many roots do most of thi
nerves have ? 582. How many pairs of cranial nerves, and what are their names ? 
S26
HITCHCOCK'S   ANATOMY
FiG. 311.
terior portion of the base  of  the brain, and are distributed
upon the  mucous membrane of the  nostrils ;  especially that
part ofit which is spread out upon the turbinated bones.
                                       584.  Optic—The  optic
                                    nerves arise at  a point  be-
                                    hind  that where the olfac-
                                    tories  are  given  off,   and
                                    about  one inch  from   this
                                    point  come   together   and
                                    form a ganglion ; after  this
                                    they are again separated and
                                    proceed   to   the  posterior
                                    portion  of  each  eye-ball,
                                    where they   are  expanded
                                    into a membrane, called the
                                    Retina.    (Fig.  311.)
                                       585.  Motores Oculoruei.
                                    —The third  pair  are  also
                                    given off  from  the  base of
                                    the brain  near  to the pons
                                    varolii,  and are  sent to  a
                                    part of  the muscles  of the
                                    eye.
                                       586.  Trochleares.—The
                                    trochleares have nearly the
                                    same origin as the last-men-
                                    tioned pair, and are distrib-
                                    uted to  the superior oblique
                                    muscles of each  eye.   (Fig.
                                     312.)
   587.  Trifacial.- The fifth  pair, or trifacial,  is the largest
of the cranial nerves.   It is analogous to  the spinal nerves  in
  A View of the Second Pair or Optic, and
the Origin of Seven other Pairs.  1, 1, Globe
of the Eye.  The one on the left hand is per-
fect, but that on the right has  the Sclerotic
and Choroid removed to show the Eetina.  2i
The Chiasm of the Optic Nerves.  3, The
Corpora Albicantia. 4, The Infundibulum.
5, The Pons Varolii.   6, The  Medulla Ob-
longata. The figure is on the  Eight Corpus
Pyramidale.  7, The  Third  Pair,  Motores
Oculi.  8, Fourth  Pair, Pathetici.  9, Fifth
Pair,Trigemini. 10, Sixth Pair, Abducentes.
11, Seventh Pair, Auditory and Facial. 12,
Eighth Pair, Pneumogastric,  Spinal Acces-
sory, and Glosso-Pharyngeal. 13, Ninth Pair,
Hypoglossal
 583. Give the anatomy of the olfactory nerves.  5S4. Describe the optic nerves. 5>5.
Describe the motores oculorum.  586. Give the anatomy of the fourth pair.  5S7. De-
scribe the trifacial. 
AND   PHYSIOLOGY,
32,
Fig. 312.
  A View of the Third, Fourth, and Sixth Pairs of Nerves.  1, Ball of the Eye, the Eec-
tus Externus Muscle being cutand hanging down from its origin.  2, The Superior Max-
illa,  3, The Third Pair, or Motor Oculi, distributed to all the Muscles of the Eye except
the Superior Oblique and External Eectus.   4, The Fourth  Pair, or Patheticus, going to
the Superior Oblique Muscle.  5, One of the Branches of the Fifth.  6, The Sixth Pair,
or Motor Externus, distributed to the External Eectus Muscle.   7, Spheno-Palatine
Ganglion and Branches.  8, Ciliary Nerves from the Lenticular Ganglion, the short Eoot
of which is seen to  connect it with the Third Pair,
  A View of  the  Distribution of the Tri-                  Fig.  313,
facial, or Fifth Pair. 1, Orbit.  2, Antrum
ofllighmore.  3, Tongue.  4, Lower Max-
illa.   5, Eoot of  Fifth Pair, forming  the
Ganglion of Casser. 6, First Branch, Oph-
thalmic.  7,   Second  Branch,  Superior
Maxillary.   8, Third Branch,  Inferior
Maxillary.  9, Frontal Branch,  dividing
into External and  Internal Frontal at 14.
10, Lachrymal branch, dividing before en-
tering the Lachrymal Gland.  11, Nasal
Branch.  Just under the figure is the long
Eoot of the Lenticular or Ciliary Ganglion,
and a few of  tho  Ciliary Nerves.   12, In-
ternal Nasal, disappearing  through  the
Anterior Ethmoidal Foramen. 13,  Exter-
nal  Nasal.   14,  External and  Internal
Frontal.  15,  Infra-Orbitary  Nerve.  16,
Posterior Dental Branches.   17,  Middle
Dental  Branch.    18,  Anterior  Dental
Nerve.  19, Terminating Branches of In-
fra-Orbital, called  Labi.'il and Palpebral.
20, Subcutaneous Malre,or Orbitar Branch.
21, Pterygoid or Recurrent, from Meckel's
Ganglion.  22, Five Anterior Branches of
Third of Fifth, being Nerves of Motion,
and  called Masseter, Temporal,  Ptergoid,
and  Buccal,  23,  Lingual  Branch joined at an acute angle by the Chorda Tympani.  24,
Inferior Dental Nerve terminating' in 25. Mental Branches.   20, Superficial Temporal
 Nerve.  27, Auricular Branches.  28, Mylo-hyoid Branch.
 
HITCHCOCK'S   ANATOMY
FiG. 314.
  Distribution of the Fifth Pair of Nerves,  a, Submaxillary Gland.  1, Small Root or
tho Fifth Nerve.  2, Casserian Ganglion. 3, Ophthalmic Nerve.  4. Upper Maxillary
Nerve.  5, Lower Maxillary Nerve.  6, Chorda Tympani.  7, Facial Nerve.
that  each nerve  arises by two  roots,  and afterwards,  before

distribution, forms the Casserian ganglion.   This ganglion is

separated into three branches : the ophthalmic, which supplies

                                        the region of  the  eye  and

                                        nose ;  the superior  maxil-

                                        lary,  supplying   different

                                        parts  of the face from  the
                                        temporal  musclb  to   tlj
                                          A View of the Origin and Disiribu
                                        tion of the  Portio Mollis of the Sev-
                                        enth Pair, or Auditory Nerve.  1, The
                                        Medulla Oblongata. 2, The Pons Var-
                                        olii.  3, 4, The Crura Cerebelli of the
                                        Eight Side.  5, Eighth Pair. 6, Ninth
                                        Pair. 7, The Auditory Nerve distrib-
                                        uted to the Cochlea and Labyrinth.
                                        8. The Sixth Pair. 9, The Portio Dura
»fthe Seventh Pair.  10. The Fourth Pair.   11, The Third Pair.
 
AND  PHYSIOLOGY.
329
Fig. 316.
lips, including the upper teeth

and  the   inferior  maxillary,

sending its  branches  to  the

tongue, cheeks^  and anterior

portion of the face.

   588.  Abducentes. —The

sixth pair, abducentes, are sent

from the  medulla oblongata to

the external muscle of the eye.

   589. Facial.—The facial

nerves have  their  origin  in

common  with  the   last  pair.

They join  with  some  of  the

branches  of the fifth pair, and

distribute  their  filaments  to

some of the muscles of the face.

   590. Auditory.—The au-

ditory nerves, as their names

imply,  are sent  to  the  ear.

They  enter  the  internal  ear

  Origin  and Distribution of  the Tenth
Pair of Nerves.  1, 3, 4. The Medulla Ob-
longata.  1 Is the Corpus  Pyramidale of
one side.   3, The Corpus Oblivare.  4, The
Corpus Eestiforme.  2, The Pons Varolii.
5, The Facial Nerve.  6, The Origin of the
Glosso-Pharyngeal Nerve. 7, The Gang-
lion of Andersch.  8. The Trunk of the
Nerve.  9, The Spinal Accessory  Nerve.
10, The  Ganglion of the  Pneumogastric
Nerve.  11, Its Plexiform Ganglion.  12,
Its Trunk.  13, Its Pharynseal  Branch
forming the  Pharyngeal Plexus (14), as-
sisted  by a  Branch from the  Glosso-
pharyngeal (S), and one from the Superior
Laryngeal Nerve (15). 16, Cardiac Branch -
es. 17, Recurrent Laryngeal Branch.  18,
Anterior  Pulmonary Branches.  19, Posterior Pulmonary Branches.  20, Esophageal
Plexus.   21,  Gastric Branches.  22, Ori.in of the Spinal Accessory Nerve.  23,  Its
Branches distributed to the Sterno-Mastoid Muscle.  24, Its Branches to the Trapezius
Muscle.
588. Describe the abducentes.  589. Describe the facial nerves.  590. Describe the au-
tory nerves. 
330
HITCHCOCK'S   ANATOMY
after  receiving  fibers from  the  facial,  and there divide into

two branches,  which are distributed in the irregular labyrinth

of the ear.

   591.  Glosso-Pharyngcal.—Theglosso-pharyn,ealmakes

the  ninth pair, and is sent  to the mucous surface of the fauces,

tongue,  tonsils, and mucous glands of the mouth.

   592.  Par  Vagi, or Pneumogastric  — The tenth pair, pai

vigum,  spring from the  medulla  oblongata,  and after  giv-

               Fig.  317.                ing branches  to several  of

                                       the cranial nerves,  are dis-

                                       tributed  upon   the  heart,

                                       lungs, stomach,  and nearly

                                       all the organs of the  tho-

                                       rax and abdomen.

                                          593.  Spinal Accessory.

                                       —The  spinal  accessory

                                       takes  its  origin  from  the

                                         The Anatomy of the side of the Neck,
                                       showing the Nerves of the Tongue.  1,
                                       A  Fragment of the  Temporal Bona
                                       containing the Meatus Auditorius Ex-
                                       ternus,  Mastoid, and Styloid Process.
                                       2, The  Stylo-Hyoid Muscle.  3, The
                                       Stylo-Glossus.  4, The Stylo-Pharyn-
                                       geus. 5, The Tongue.  6, The Hyo-
                                       Glossus Muscle; its two portions.  7,
                                       The  Genio-Hyo-Glossus Muscle.  8,
                                       The Genio-Hyoideus: they both arisa
                                       from the inner surface of the Symphy-
                                       sis of the Lower Jaw.  9, The Sterno-
Hyoid Mnscle.  10, The Sterno-Thyroid.  11, The Thyro-Hyoid, upon which the Thyro-
Hyoidean Branch of the Hypoglossal Nerve is seen ramifying.  12, The Omo-llyoid
crossing the Common Carotid Artery (13), and Internal Jugular Vein (14). 15, The Ex.
ternal Carotid giving off its Branches.  16, The Internal Carotid.  17, The Gustatory
Nerve giving off a Branch to the Submaxillary Ganglion (18), and communicating a little
further  on  with toe Hypoglossal Nerve. 19, The  Submaxillary, or Wharton's Duct
passing forwards to the Sublingual Gland. 20, The Glosso-Pharyngeal Nerve, passing in
behind the  Hyo-Glossus Muscle.  21.  The Hypoglossal Nerve curving around the Oc-
cipital Artery.  22, The Descendens Noni Nerve, forming a Loop with (23) the Commu-
nicans Noni, which is seen to be arising by filaments from the Upper Cervical Nerves.
24, The Pneumogastric Nerve, emerging  from between the Internal Jugular Vein and
Common Carotid Artery, and entering the Chest.  25, The Facial Nerve, emerging from
the Stylo-Mastoid Foramen, and crossing the External Carotid Artery.


         Describe the glossopharyngeal, par vagum. and spinal accessory.
 
AND  PHYSIOLOGY.              331
upper part of the  spinal  column  and  afterwards enters  the
cranium.   After keeping  company with the  p;ir vagum for a
part of its course, it is distributed to some of the muscles upon
the head and face.
   594, Lingual.—The lingual  nerve plunges  its  branches
deeply  into the fibers of the tongue, and communicates  with a
branch  of the trifacial.
                                                Ftp SI8
   595. Spinal  Cord.—The spinal cord        a
is that portion of the cerebro-spinal  axis          1     ,
contained within  the channel made bv          \l\
the foramina, or openings of  the  verte-          *>^\.....C
bra.  It extends  from  the  medulla  ob-       _~~-J;V
longata just  at the base of the skull, to           .   y^
the second  lumbar vertebra, and  has an           (l f
average diameter  of  half an inch.   It   Portion of the spinal Cord
      ~                                   and Origin of  one Pair of
has the general appearance of a flattened  Nerves,  a, Spinal  Cord,  b,
      d.           7      .      ....      Posterior Eoot. c, Ganglion.
    .  but on a closer inspection  it ap-  d> Anterlor Rl>ot.  e> Trunk
pears to be made up of two smaller cords,  formefl b? both-  /• Branch.
called the lateral cords, nearly separated by two clefts, called
the anterior  and posterior median  fissures.   This cord  is  not
perfectly uniform in its size, but presents two enlargements,
one at the point where the nerves are given  off to the  upper
extremities,  and the other near the lower end of the cord.
   596. Microscopic  Structure  of  the Spinal lord.—In
anatomical structure we find the spinal cord and spinal  nerves
are made up of two kinds of nervous  matter,  the white and
the gray, and also  that  each pair of these  nerves arises by
an anterior and a posterior root.   The  posterior  root is made
up of gray nervous tissue, and is called the  sensitive root,'
since  it gives the sense of feeling to the parts where it  is dis-
tributed ; the anterior root of white fibers  is  called the mo-
tor root, because it imparts motion to the different muscles of
 594. Describe the lingual. 595. What is the spinal cord ?  llow many fissures has the
spinal cord?  How many enlargements?  596. What is tho microscopic structure of tb«
spinal cord?  Which is the sensitive and which the motor root? 
332            HITCHCOCK'S  ANATOMY
the body.   A ganglion is found upon the posterior root, just
before it unites  with the anterior.
   59T. Origin  of the  Spinal Xcrvc s.—Between  each  of
the vertebrae the spinal nerves are given off.   These are made
up of fasciculi, and each  fasciculus of distinct fibers which
somewhat resemble muscular fiber.  They arise on each side
of the cord by two roots,  one given off from the anterior and
the other  from the  posterior  part of  the lateral cords ; the
anterior root being the one that is designed to produce mo-
tion, and the posterior giving  sensation to the parts on which
it  is distributed.   These two roots  unite as  soon as they  have
fairly left the spinal cord,  after which they proceed as a single
nerve.  (See Fig. 318.)
      Fig.  319          598. Groups of Spinal .\ervcs.—These
                     nerves are grouped together, and have
                     the same name as the  groups of verte-
                     brae  in which they are located.
 8 Cervical.
12 Dorsal.
5 Lumbar.
6 Sacral.
                     The last nine are  additional, or  supple-
                     mentary to the spinal cord, and not prop-
                     erly a portion of it.   They are called
                     the cauda equina.
                        599.  Plexuses .—Most of these nerves
                     are grouped  together soon  after leaving
                     the  spinal column,  each  group  being
                     called a plexus  (from  the Greek  " to
                     weave"), which is simply a net-work of
                Although there is to the naked  eye a com-
plete interlacement and an apparent loss  of fiber, yet by the
microscope these fibers can be distinctly traced through  the
whole  mass, with  the exception  of a  few which are inter-
changed for purposes to be described hereafter.   After emerg-
 Diagram to show the De-
cussation  (crossing  from
side to side) of Nerve Fi-
bers in a Nerve.
nervous fibers
 597. Give the origin of the spinal nerves. 598. State the groups of the spinal nerves.
599. Describe the nature of the plexuses. 
and   physiology

           Fig. 320.
333
                               Nervous System.
  a, Brain,  b, Little Brain,  c, Spinal Marrow,  d, Facial Nerve,  e, Brachial  Plexua,
caused by the union of several Nerves coming from the Spinal Marrow.  /, Median Nerve.
g, Cubital Nerve,  h, Internal Cutaneous Nerve of the Arm.  i, Eadial  and Musculo-
cutaneous Nerve of the  Arm. j, Intercostal  Nerves,  k, Femoral  Plexns.  c, Sciatic
Plexus,  m, Tibial Nerve,  n, External Peroneal Nerve ;  o. External Saphenous Nerve. 
334
HITCHCOCK'S  ANATOMY
ing from the plexuses,  the nerves proceed to their destination
and receive names,  many of which are the same as the arteries
which they accompany.
   600.  Cervical  Plexus — Brachial   Plexus  — Lumbar
Plexus — Sacral  Plexus.—The cervical  plexus is made up of
the four upper cervical nerves,  and the brachial plexus of  the
Fig. 321.                           Fig. 322.
2, 2, The Median Nerve.  3, The Ulnar Nerve. 4,    Nerves of Front of Fore-Arm. (^
The Branch to the Biceps Muscle. 5, The Nerves  Median Nerve.  2, Anterior Branch
of Wrisberg.  6, The Phrenic Nerve  from the  of Mnsculo-Spiral or Uadial Nerve.
Third and Fourth Cervical.                   8, Ulnar Nerve. 4, Division of Me-
                                       dian  Nerve in the Palm  to the
     Thumb, First, Second, and Eadial Side of Third  Finger.  5,  Division of Clnw
     Nerve to Ulnar Side of Third and both Sides of Fourth  Finger.
600. What nerves go to make up the cervical and brachial plexus t 
                  AND  PHYSIOLOGY.              335

four lower cervical and upper dorsal nerves, and they give off
their branches to the  upper part  of the  body.   The  lumbar
plexus is made up of the last dorsal nerve and the five lumbar
nerves ;  and the sacral plexus  of a branch of the last lumbar
and the  upper sacral  nerves.   These supply the portions  of
the body below the loins, and the  superficial parts of the body
between the loins and upper part  of the chest.
           Fig. 323.                          Fig. 324.
                              A View of the Anterior Crural Nerva
arid Branches.  1, Place of emergence of the Nerve under Poupart's Ligament.  2,
Division of the Nerve into Branches.  3, Femoral Artery.  4, Femoral Vein.  5,
Branches of Obturator Nerve.  6, Nervus Saphenus.
Describe the lumbar plexus. 
336           HITCHCOCK'S   ANATOMY

   601. Direction of the  Nerves.—The largest and most im-
portant nerves follow the same general direction as the larger
blood-vessels, and generally are in close proximity to them.

   602. Motor  Nerves—Mode  of   Termination—Pacinian
Corpuscles.—The nerve fibers which  go from the  anterior
columns of the spinal cord terminate in the fleshy  portions of
tie muscles, because they are the motor nerves, or those ex-
 Little Too.  8, Branch to
Mween Fourth and Fifth Toes.  9, 9, 9, Digital Branches to remaining
  10, Branch to Internal Side of Great Toe.
 C01. Give the general direction of the nerves through the body. 602. Where d_ cha
motor nerves terminate ? 
AND  PHYSIOLOGY.
337
citing  motion.   Those from  the posterior  columns  spread
through the surface of the body, giving sensation to the skin.
The mode, however, in which they terminate is not always the
same.  As far as at present is known, they seldom terminate
in a free or single  extremity,  but  in loops, returning into
themselves, or joining with  other fibers.   And it is  an  an-
atomical  fact  that the nerve  tubes  do  not anastomose  one
with the  other, as is the case among  the  blood-vessels;  but
each tube discharges  its own  duty,  and not that of another
under  any  circumstances.   In  the  skin  of the  hand  and
foot they terminate in minute oval bodies from  the  rfsth to
the TTot'i of an inch in length, and from one twenty-sixth to
one twentieth of an  inch in  breadth, called Pacinian  Cor-
puscles (from Pacini, their discoverer), and are attached to
the branches and extremities of the  nerves very much in the
same  manner  as some kinds of fruit are attached  to their
boughs.   (Fig. 326.)  Of these, there are about six hundred
in the hand and a somewhat smaller number in the foot.  They
are composed of connective  or  areolar tissue in from twenty
to sixty bands, with  interspaces containing a serous fluid,  and
are attached to their nervous  twig by a rounded peduncle
The function of these bodies is  entirely unknown.


   603. Sympathetic  System — Its  Size — Connection
with   Spinal  Nerves—Destination  of   its  Branches.—
Besides  the cerebro-spinal  center,  there  is another  organi-
zation of nervous  tissue which  is  called the  Sympathetic
Nerve, or Ganglionic System, and  is to be regarded as an
appendage of the spinal nerves.   It is  of  very limited size,
consisting of mere reddish threads of nervous matter and oval
bodies called ganglia, never  so  large as peas.  These  ganglia
and nerves extend along each side of the spinal column from
 State the manner in which they terminate.  Give a description of the Pacinian cor
puscles. 6U8. What is said of the structure of the sympathetic system? 
338
HITCHCOCK'S   ANATOMY
Fig. 327.
turn. 84,  Globe of the Eye.  35, 36, Cavity
       the atlas to  the  coccyx,

       communicating  with  all

       the spinal nerves by two

       small   fibers  (see  Fig.

       328), and giving branches

       to all the internal organs

       and   viscera.    Branch e.3

       and   ganglia    are   also

       found between  the  bones

       of  the  cranium  and the

       face.      The    branches

       which are given off to the

       internal  organs  accom-

       pany the  arteries  to the

       same, forming a net-work

        Great Sympathetic Nerve.   1,
       Plexus on the Carotid Artery in the
       Carotid Foramen.  2,  Sixth Nerve
       (Motor Externus).  3, First Branch
       of the Fifth, or Ophthalmic Nerve.
       4, A Branch on the Septum Narium
       going to the Incisive Foramen.   5,
       Eecurrent Branch, or Vidian Nerve
       dividing into the Carotid and Petro-
       sal Branches.  6, Posterior Palatine
       Branches.  7, Lingual Nerve joined
       by the Chorda Tympani.  8, Portio
       Dura of the Seventh Pair.  9, Supe-
       rior Cervical  Ganglion.  10, Middle
       Cervical Ganglion.  11, Inferior Cer-
       vical Ganglion.   12,  Boots of the
       Great SplanchnicNerve arising from
       the  Dorsal  Ganglia.   13,  Lesser
       SplanchnicNerve. 14, Eenal Plexus.
       15, Solar Plexus.  16, Mesenteric
       Plexus.  17,  Lumbar  Ganglia.  IS.
24     Sacral Ganglia.  19, Vesical Plexus.
       20,  Eectal  Plexus.   21, Lumb::r
       Plexus (Cerebro-Spinal).  22, Eec-
       tum.  23, Bladder. 24, Pubis.  25,
       Crest of tho Ilium.  26, Kidney.  27,
       Aorta.  28, Diaphragm.  29, Heart.
       80, Larynx. 31, Submaxillary Gland.
       32. Incisor Teeth.  33, Nasal Sep-
of the Cranium.
Where does it give its branches? 
AND   PHYSIOIOGY.
339
Fig. 328.
       Boots of a Dorsal Spinal Nerve, and its union with the Sympathetic.
  c,c, Anterior Fissure of the Spinal Cord,  a, Anterior Eoot.  p, Posterior Eoot, with
its Ganglion,  a', Anterior Branch,   p', Posterior  Branch.  «, Sympathetic,  e, IU
Double Junction with the Anterior Branch of the Spinal Nerve by a White and Gray
Filament.
of communication around the vessels.   And  as all the inter-
nal organs, especially those called vital, are supplied with this
nerve, and not directly from  the  cerebro-spinal center, it is
hence called  a nerve of organic life.
   604.  Sympathetic Ganglia—Each of  these  ganglia  may
be considered as  a  nervous center  sending  forth  strands in
three directions;  1st, to join  the spinal  nerves  in their dis-
tribution ;  2d, to the spinal cord itself;  3d,  to the next  sym-
pathetic ganglion above.
604. What may each of these ganglia be considered as? 
340           HITCHCOCK'S  ANATOMY

  605.  Groups of Sympathetic  G a n g 1 i a .—These ganglia
are  grouped together according to the  locality, to which their
branches are distributed.  Thus we have the Cranial ganglia,
Cervical ganglia,  Thoracic  ganglia.  Lumbar  ganglia,  and
Sacral ganglia.  Besides these there are several large  plex-
uses which  have received  distinct  names,  although a  great
number of small ones have not received  any names.   Of the
most  important  ones  we may name the  Pharyngeal, in the
immediate  vicinity  of the Pharynx, the  Cardiac  lying upon
the  heart, and the  Solar, between the  liver and stomach, or,
as is more commonly known,  the pit of the stomach.
  606.  The Solar  Plexus.—The Solar Plexus seems  to be,
as its name implies, a sun or center for nervous power  to the
intestines, since branches from this plexus accompany the ar-
teries  to  the  vital  organs, where they  subdivide  again and
again, and enter their coats and substance.


      FUNCTIONS  OF THE  NERVOUS  SYSTEM

  607. The functions of the Nervous System are the most
important and delicate  of any in the body.   1.  The  Brain
affords a seat and center for life and intellect.   2. The nerves
are inlets for all the senses to the sensorium or seat of  sensa-
tion.   3.  They are  the medium of  all the  movements  of the
body,  voluntary  and involuntary.    4.  They  establish and
maintain a sympathy between all the parts of the  body, and
equalize all the vital forces.  5. They  preside over the in-
voluntary functions, such  as the  circulation of the blood, di-
gestion, respiration, and reflex actions.
  608.  Intellect  and  Will  located  in   the   Brain.—
Voluntary  Movements   dependant   on    the   Brain. —
The  whole  Brain  not   essential.— The  Intellect  and
 6D5. How are the sympathetic ganzMa grouped together?  What is said of the sym-
pathetic plexuses? 606. Describe the solar plexus. 607. What are the five principal func-
tions of the nervous system ? 
AND  PHYSIOLOGY.
341
Will evidently reside  in the  brain  (cerebrum),  and  re-
quire that this organ  should be in  a healthy  state, since,
if any  disease affects its  whole  substance, their power is
destroyed.   Voluntary muscular movements depend  on  a
sound and healthy brain, although reflex movements, and  the
motion  necessary  to  sustain  animal life, are  often  carried
on  in some animals for a considerable time, when  they are
born without a brain.   But the whole brain  does not seem to
ba absolutely essential to life  and mental operations, for many
instances  are mentioned, where a considerable portion of  the
brain has been removed by accident, such as a bullet  or iron
bar being shot through  the head  followed by  a discharge
of  nervous matter:  and  yet  the  persons have  lived  for
years subsequent  to the accident  in  as  sound a  condition as
ever.

   608a.  Necessity of  two Cerebral  Hemispheres.—One
may  be injured,  and  not  the  other.—The reason  of  the
division of the brain into lobes or hemispheres is not so easily
understood.  Perhaps  it may be  that so large an organ of so
soft a  substance  could not easily sustain  its own weight, es-
pecially when  reclined on one side, and at the same time
properly  perform  its functions.   A more  probable reason,
however,  is this.   It  is  a well-known fact, that one  of  the
hemispheres may be diseased  or injured,  so  as to perform its
functions  imperfectly, and  yet the other hemisphere  be in its
ordinary  healthy  state.    Also one hemisphere may be so
much affected,  that the opposite side  of the whole  body is
paralyzed  in motion  or sensation,  or  both.   It  then seems
reasonable to suppose, that, since the brain would be so liable
to injuries, it was made in two portions, so  as to prevent  tl 3
entire destruction  of life by an injury to one of the hemis
spheres.
 608. Where are the intellect and the will located ?  What movements depend on the
brain? Is the whole brain absolutely essential for intellection ? 608 a. Whyarether*
probably nvo hemispheres to the brain? 
342
HITCHCOCK'S   ANATOMY
  609.  To  secure Precision in  all  Voluntary  Actions,
—In Draper's Physiology is found another hypothesis for the
division of the brain into two parts: this is to secure precision
in the efforts  of the  intellect  and will.   "For there is no
doubt," he  says,  "that the hemispheres  have not only the
power of acting separately,  but also conjointly ; thus there is
no student but must  have observed, when busily engaged in
i >ading, that his mind will wander off to other  things,  though
hj may mechanically  cast his eye over  page  after page;  and
the same may occur in listening to a lecture or sermon.  But
though the insane man may indulge in two synchronous trains
of thought,  he never  indulges in  three,  for the simple reason
that he has not three  hemispheres to do it with, the  same re-
mark  applying  to  the sane man in the accidental wandering
of his thoughts."
  610.  ThongM,  Memory,  and  the  Reasoning Powers
require a  Sound  Brain.—As already mentioned, the brain
is not the seat of motive power :  this does  not originate here,
although voluntary movements are controlled  by  it.   But
automatic or reflex movements, such as the  twitching  of the
muscles of  the  leg and foot,  when the sole  of the  foot  is
tickled  with some  slightly  irritating substance, are entirely
beyond  the  control of the cerebrum or will, since  they take
place  nearly as well in a person who is  asleep or stunned  by
a blow, or even when  the nerves  of sensation and motion are
paralyzed.   Thought, memory, reasoning, and  all the intel-
lectual  states demand a healthy  and  a sound  brain for their
perfect  action,  while  the ordinary muscular movements  and
the functions  of respiration,  circulation,  and digestion, are
dependent upon the  Spinal  Cord, Sympathetic Nerve,  anc
Cerebellum.
  611.   Definition  of  Sleep. —Need  of  Sleep. —Sleep,
l- tired  nature's sweet restorer," is a  state of the body, in

  609. How can  two hemispheres secure a precision in voluntary actions ?  010. Are
reflex movements under the control of the brain ? What powers of mind are dependen!
on the cerebrum ? 
AND  PHYSIOLOGY.
34.
   which there is a more or less perfect suspension  of the activ-
   ity  of the  brain.   The  functions  of digestion, secretion, and
   respiration,  proceed during  the soundest  sleep,  though with
   less activity than during the wakeful state.   In many cases,
   however, the functions  of the  brain do not entirely cease, as
   is seen in the phenomena of dreaming, where the brain seems
   to  be actively  at work,  but  the senses and animal functions
   are quiescent.  Sleep is demanded by all  animals to  procure
   r^st to the different organs of the body, and in health it comes
   to  all, though in different degrees  of soundness, but generally
   the greater the exhaustion, the more complete the sleep.
      612.   Periodical  Tendency of Sleep.—The  Will  can
   for  some  Time  overcome  Sleep.—The tendency  to sleep
   is  periodical.   All persons feel an inclination to sleep during
    some portion of the twenty-four hours, and during the night.
   if health be good and  nature not perverted.   Some strong
   intellectual effort, however,  or some  powerful  emotion, will
   overcome drowsiness  for a  long  time, as in  the case of the
   student working out a difficult problem, or a  mother watching
   her sick child.  But when the problem  is mastered,  and the
   child has safely passed the crisis,  sleep comes on with irresist-
   ible force.   Cases  occur constantly to  show that the brair
   must have its repose in spite of intellectual  effort or danger.
    It is related that boys wearied out with continued labor in the
   battle  of the Nile, slept during a part  of the action, and  in
   another naval  engagement, a captain slept two hours  within a
   yard of his  largest gun, which was kept  in action during the
   whole time.   Indians at the stake of torture will sleep on tho
    least remission of  agony, but awake a3 soon  as  it is renewed
    again.   And we  learn  that a most barbarous punishment is
    still practiced  in China, that of keeping  a victim awake until
    ht> dies of sheer exhaustion.   The distress of it is said  to be
•   terrible.
     611 What is sleep?  What powers are inactive during sleep, and what processes are
    carried on during it? What is sleep necessary  for?  612. State the fact of a periodical
    tendency to sleep.  Can the will overcome sleep?  For how long a time  can it do it?
    Relate the facts mentioned.          . c + 
344
HITCHCOCK'S   ANATOMY
   613. Inducements  to  Sleep.—Sleep  sometimes  under
 the  Control  of  the  Will.— Ordinarily darkness and si-
 lence promote sleep;  but if a person once becomes habituated
 to noise during slumber—if it  be a continuous one—he can
 not  sleep well without it.  Thus persons living in  the vicinity
 of forges and noisy mills can not readily sleep elsewhere.  And
 a monotonous repetition of  sounds is a most  favorable provo-
 cative to sleep, the cause of which  is that other  impressions
 can  not so readily be  made  on the mind,  and thus the sleeper
 is less easily roused.   A dull reader on a dull  subject has a
 most ready effect in producing sleep, as well as the sound of
 a distant waterfall, or the rustling of leaves in a forest. Rub-
 bing many parts of the skin, cr combing  the hair by another
 person,  will  often cause drowsiness,  and  sometimes  sleep.
 Again a person can sometimes put himself to  sleep, if restless,
 by a monotonous intellectual effort, such as the rehearsal of a
 Latin paradigm, or counting the rain-drops, as they fall  from
 the eave trough into the spout.

   614.  Effect   of Habit  on  Sleep.—The  effect of habit is
 powerful in producing sleep.  Let one be  accustomed to retire
 early—in accordance with  nature—and  sleepiness  comes at
 the usual hour for retiring; but if a person  for a  series of
 years is in the habit of sleeping the latter part  of the  night
 and  early in the morning, it is almost  impossible  for him to
 sleep early in the  night.   Those persons who, like sailors,
 soldiers, and watchers, are obliged to catch  sleep when they
 can get it, and then only in small amounts at  a  time, sleep
 with but little difficulty when the  opportunity presents itself.
 Captain  Barclay,  who walked one  thousand miles in as many
consecutive hours,  had such  a power over himself, that he  w: 3
asleep the moment he lay down.   Some physicians  have  tha
same power.

  613.  What are the common inducements to sleep?  Do any persons ever require a
noise, in order to sleep soundly ? What effect does rubbing or chafing certain parts of
the body have upon sleep?  Can sleep ever be brought about by an action of the will?
How ?  614. What effect has habit upon producing sleep ? Mention the case of Captain
Barclay. 
AND  PHYSIOLOGY.
343
   615.  Preventives  of  Sleep.—Any unusual noise or place
of sleeping will prevent or disturb the sleep of many persons.
Thus the singing  of a mosquito keeps many a man awake a
long time.  But if a noise  be repeated often,  it  will have
no effect of this kind.  The college Freshman for the few first
mornings is readily awaked  by the first stroke of the early
prayer-bell, but in  a short  time it has no effect  whatever
" A gentleman who had taken his passage on board a man of
war, was aroused  on  the  first  morning by the report of the
morning gun, which chanced to be  fired just above his head;
the shock was so violent as to cause him to jump out of bed.
On the second morning he was again awakened, but this time
he merely started  and sat up  in  bed;  on  the third morning
the report had  simply the effect of causing him  to open  his
eyes for a moment and turn in his bed ;  on the fourth morn-
ing it ceased to affect him at all,  and his  slumbers  continued
to be undisturbed so long as he remained on board."
   616.   An  Absence  of Accustomed   Sounds  prevents
Sleep.—The reverse of  this  sometimes happens, if there be a
cessation  of monotonous and unaccustomed sound,  by which
sleep was induced.   Thus a person who  has  been read  or
](reached to sleep,  will awake if the reader or preacher pause
or stop, before  any disturbance  is made, and a person asleep
in a railway train,  will often awake on the stopping,  or even
on the slackening  of the train.
   617.  Amount of  Sleep.—The amount  of sleep  necessary
for man, varies exceedingly, being affected  by the conditions
of age,  temperament,  habit,   and exhaustion.    Infants and
very old people sleep the most.   The  former require it that
the constructive process may go on as  uninterruptedly  ;>3
possible,  and they  generally sleep three fourths  of  the time.
The latter need a large  amount  of sleep, because the vital
energies are so feeble.
 615. What will often easily prevent sleep ? Instance the  college Freshman and  the
gentleman on the man of war.  616. How does an  absence of accustomed sounds affect
6leep ? 617. What amount of sleep is necessary ? What ages sleep the most': 
346
HITCHCOCK'S   ANATOMY
  618.  A Lymphatic Temperament a  Sleepy one.—Persons
of a lymphatic temperament, those who  are  seldom excited,
sleep more  than  those  of a  nervous  temperament,  who are
always rapid and quick in their movements.   The former live
slowly,  and  but comparatively little waste is going on, and
consequently the brain is all the time nearer to sleep  than in
the latter class, whose brain, when awake, is very active, and
V ien asleep, is asleep very soundly.
  619.  Effect of  Habit  on the Amount  of  Sleep—Re
markable Cases.—The amount of sleep  is greatly modified
by habit, and often the briefest sleepers have been men of the
greatest activity.   If a person acquire the habit  of sleeping
but little, he must sleep very profoundly, so that what is lost
in quantity, is made up in  intensity.   The  habit of  taking
but little sleep, however, is not a sure indication that a proper
amount of it has  been secured.    Frederic  the  Great, and
John Hunter slept but five hours out of the twenty-four ; and
General Elliot, engaged in the defense of Gibraltar, and Na-
poleon,  often slept  but four hours out  of the  twenty-four.
The general rule,  however,  seems to  be that  man  should
take from six to eight hours of the twenty-four, for uninter-
rupted  slumber.  Women  in general  seem to require rather
more.
  620.  Mode of  Access of  Sleep.—To some deep comes on
instantly when the will determines upon it, but to others it is
a gradual and tedious process, especially in ill  health,  or an
excited  mental state.  Many physicians drop asleep as soon a?
the head touches the pillow,  and  are  aroused by no ordinary
sound, such as the tread of another  person in the room, or
the shutting of a door, but wake as soon as the night-bell  ia
rung.   Sir  E. Codrington, when  a young  man  in  the nava) t
service, was very active at one time in looking out for signals,

  61S. What are the sleepy temperaments?  What the  wide-awake ones? 619. IIow
does habit affect the amount of sleep ? State some remarkable eases.  What is an average
amount of sleep for men ?  How much for women i  620. Row does sleep come ow'
Give examples. 
AND  PHYSIOLOGY.
34 7
 and was employed during  his waking hours in this business.
 Hence his sleep was very solid,  and he was  roused by no or-
 dinary sound, but his comrades amused themselves by  whis-
 pering the  word "signal" in his ear, when he was at once
 aroused and fit for duty.

   621.   Functions  of  the  Cerebellum___The  Cerebellum
 does not seem to be in any manner  directly connected with
 the phenomena  of mind.   But  it seems designed simply  for
 the purpose of combining the actions of different muscles, or
 presides  over the coordination  of voluntary muscular  move-
 ments, as in walking, speaking, and similar  actions requiring
 several  sets of muscles to be used at the same instant.   Ac-
 cordingly in animals, which  possess  the greatest variety of
 movements, we find the largest cerebellum.
   622.  Effects when  Removed  from  Animals.—The Con>
 trolling  Power of  Muscular   Motions.—When this organ
 has been removed from some of the lower animals, it was found
 that they  could not  control  their  movements.  When laid
 down they  could not  recover their erect posture, and  when
 threatened with a blow, they  in vain endeavored to avoid it.
 Another phenomenon attending a wound, or removal of both
 sides  of  the cerebellum, was  the motion of the animal in a
 backward dire :tion, and the  rolling from side  to side on the
 longitudinal axis of the body,  and  keeping up this motion
 uninterruptedly, for several hours, at the rate of sixty revolu-
 tions per minute.  In some men who have been afflicted with
 a disease of this organ, an unsteadiness of gait has been ob-
 served, which  gives additional strength to the belief that the
 Cerebe'lum is the regit ator of  muscular movements.

   623.  Functions  of  the  Medulla   Oblongata.—The Me-
dulla Oblongata seems to have for its  function the sending of
nervous power to the  muscles of respiration  and swallowing,

 621. Does the cerebellum control the phenomena of mind?  What are its functions
622. What effects does Its removal cause in animals ?  How does a disease of it affect
men? 623. What operations are controlled by the medulla oblongata? 
348
HITCHCOCK'S  ANATOMY
or, in other words, respiration and deglutition  are controlled
and performed by the medulla oblongata.
  624.  Function  of the  Cerebral  Ganglia.—The series of
Ganglia, Corpora striata, Thalami optici, etc., are regarded by
Dr. Carpenter as the true sensorium in man, and this  is one
of the  most important facts established with  regard  to tho
nervous system.  A prominent reason for the belief, that tl s
brain is simply superadded to them, is seen in many instances
of children born without a brain, but with the sensory ganglia
present, where the functions of animal  life have  been carried
on for a considerable length of time.
  625.  Functions  of  the  Spinal  Cord.—The functions  of
the Spinal Cord are considered in a double aspect:  First, as
the means  of communication between the roots of the spinal
nerves,  and those parts of  the nervous  system  within the
cranium, and second, as  a center  of nervous power to pro-
duce  reflex movements  when an impression is made upon this
cord.
  626.   Function  of   Sympathetic   Nerve. — The   Sym-
pathetic Nerve "in its offices is a motor nerve to many of the
internal viscera of the body,  the heart and the intestinal canal
especially; it is also a  sensitive  nerve  to these parts, and  it
]  resides over the action of the blood-vessels of these as well
as of the other parts, where it is distributed, as of the head
and  neck, and  likewise of  all  the  principal  glands  of the
body."
   627.  Organic Functions  depend on the Spinal Cord.—-
Effect  of Pressure on  this Cord.—Almost all the func-
tions  of organic life, such as breathing, digestion, and  circu-
lation, are greatly influenced by the condition  of the  spiniA
cord, and  especially in its  connection with the sympathetic
nerve, although the brain has some controlling power.   Yet

  624 By what set of bodies are the principal  functions of animal  life carried  on? 625.
What are  the functions of the spinal cord ? 626. Give the use of tho sympathetic nerve.
627. Upon what portions of the nervous system do organic function1? depend ? 
AND  PHYSIOLOGY.
349
when we are asleep, or the brain  is  stunned by a blow, the
organic functions are carried on as in  the state of the activity
of the brain, though with far less energy.   And in the case
already mentioned of animals born without  a brain, life (or-
ganic) may be sustained for a considerable time merely by the
functions of the  spinal cord.   If this cord be severed near the
head, or even if it be compressed, life soon  ceases.   This is
the manner in which death ensues by hanging, or breaking the
neck as it is termed  ; where one vertebra is  slipped from its
place (put  out of joint), so that by the unequal contraction
of the muscles  such a pressure is made on the  cord that life
speedily becomes extinct.   And if this cord is compressed in
any portion,  sensibility and the power of motion in muscles
supplied by the  part below the  point of compression are  de-
stroyed ; and if  the  pressure  be long continued, or the cord
divided, its  vitality is for ever destroyed, although  the  parts
above it are only indirectly affected.
  628.  Sensation  Exists  Previously  to  Motion—Centri-
petal and  Centrifugal Fibers —Rate of Movement through
the Nerves.—From  the fact that one portion of  each nerve is
designed for sensation, and the other for motion,  it is probable
that sensation must exist previous to the motion of the part.
Thus, for example, if the hand be brought in contact with any
substance without any previous knowledge  of its presence, no
matter how soon the hand  may seem  to grasp it, yet the in-
terval must have been long enough  for  the sensation contact
to have passed from  the hand to the brain, and the will to de-
termine upon the condition of  the  muscles, and the order to
pass down through the white fibers  to the  hand again befoie
the grasping can take place.   Or  the same thing  may ta 3
place on receiving a  shock, or series of shocks, from a gai
vanic battery, the contractions  in this  case  being an instance
of involuntary or reflex  movement.   And  although this fact
 What is the effect of pressure upon  nr division of the spinal cord ?  628. What tv«
functions exist in each nerve? Which exists first, motion or gelation? 
350
HITCHCOCK'S  ANATOMY
seems clearly established, that one portion of each nerve trans-
mits the sensation to the brain, called the centripetal or sen-
sory, and the other conveys the order to the muscle, called the
centrifugal or  motor, yet no anatomical difference can  be de-
tected between the different fibers of the nerve.   From this
fact a German physiologist has made  a series of curious cal-
culations, as a result of which  he concludes  that nervous in-
fluence, such as the will to  move a certain muscle, travels at
the rate of 195 feet per second.
   629. Ganglia Reservoirs  of  Power.—It  has  been  sug-
gested, and with reason, that the ganglia,  abundant as they are
in the body, act as reservoirs of nerve force,  and the frequent
commissures, or union and subsequent  divergence  of  nerve
fibers, is to draw off a part of the influence which is coming
along  the centripetal fiber, and directing it into a new  chan-
nel.
   630.  Divisions  of the  Cranial   Nerves.—The  cranial
nerves may be divided, according to their function, into three
groups :
                                     Olfactory.
        Special Sense................-|   Optic.
                                     Auditory.
                                     Motores Oculorum.
                                     Patheticus.
        Motion.....................■{   Abducentes.
                                     Facial.
                                     Lingual.
                                     {Trifacial.
                                     Glossopharyngeal.
                                     Par Vagum.
                                      Spinal Accessory.
   631. The olfactory nerve is the one by which we  gain the
smell of odoriferous  substances, as they are  brought in con-
tact with this nerve in the lining membrane of the nose.

 What are the centripetal and what the centrifugal fibers of the nerves? What is a
probable rate at which the influence is transmitted through the nerves to and from tho
brain ?  629. What theory has been offered for the use of the ganglia ?  630. What thro*
groups of the cervical nerves are here given? 631-640. State the function  of each pai»
of the cranial nerves. 
AND   PHYSIOLOGY.
35J
  632.  The  optic  nerve,  as expanded in the retina, is  the
nerve of sight.
  633.  The auditory nerve receives the vibrations of the air.
which produce sound.
  634.  The motores oculorum, pathetici, and  abducentes are
the nerves which furnish motive power to the eye-ball.
  635.  The facial nerve is distributed  to  the muscles of the
face, and is the one that aids in the expressions of the emo-
tions and will, as exhibited in the countenance.   It is also the
channel of the  reflex actions in respiration, as when a person
involuntarily gasps if cold water be dashed in the face.
  636.  The lingual (hypoglossal) nerve is  necessary for the
production of articulate speech, regulating and  controlling as
it does the muscles of the tongue.
  637.  The trifacial nerve administers the sense  of touch  to
the surface of the tongue, and aids somewhat in the sense of
taste.  One branch of  it is a muscular  branch.   Another is
sent to the mucous surface of the eye,  and if it be cut off  the
eye is destroyed by suppuration.
  638.  The glosso-pharyngeal is the essential nerve of taste,
and  is closely connected in function  with the  trifacial.   It
seems also to be the nerve through which unpleasant sensa-
tions excited in the mouth are conveyed to the medulla  ob-
longata  so as to excite nausea and vomiting.
  639.  The par vagum sends nervous power  to the heart-
stomach, lungs,  and larynx,  as well as  conveys to the brain
any disagreeable sensations excited in  these organs.   Conse-
quently this  is  the essential nerve of digestion, respiration,
circulation, and opening or closure of  the  glottis under ordi-
nary circumstances.
  640.  The spinal accessory seems to be the nerve by which
the regulation of  the  muscles essential to the production of
voice is effected. 
352
HITCHCOCK'S  ANATOMY
  641.  Use  of  Spinal  Nerves. —The  use of  the  Spinal
Nerves  is to convey impressions  made at the surface  of the
body—including the extremities—to the brain, and to trans-
mit impulses to the muscles from the brain.   Both of these
influences  are  transmitted by the  same nerve  or filament,
though  in opposite directions.  From carefully conducted ex-
periments  it seems quite  probable  that the "coarse fibers'
transmit the impulses to the muscles,  and are called afferent
while the fine fibers conduct the  impressions to the brain, ana
are called efferent.  And  in the muscular nerves  the  coarse
fiber  is  proportioned  to the fine as  10 : 3.3, while in the
trunk, as it issues  from the spinal cord,  it is in  the ratio of
10  : 11.


              HYGIENIC  INFERENCES.

   642.  Tiie Nervous  System  not easily  Diseased.—1.  It
is a singular fact that  the nervous system, so delicate in its
organization and mysterious in  many of its  functions, is to
so small an extent dependent upon any particular rules for
the maintenance of its health, the  main thing necessary for
its  welfare  being an attendance  to  the general health of the
body.
   643.  It  needs Action.—2.  The  nervous  system, like all
other parts of the body, requires action  for  its health.   If a
person  has  nothing  upon which he  can  exert  his  nervous
energy, he  is liable to disease ; and no class of people are so
subject to nervous diseases as the wealthy, who are obliged to
make little exertion to procure the necessaries and luxuries ct
life.  Hence we infer that employment of some kind is indit-
pensable to the health of the nervous  system.
   644. Sleep  indispensable to its Health.—3. This system
  641. What is the use of the spinal nerves?  What is the difference in function between
the coarse and the fine fibers?  642.  Is the nervous system easily aff■•cted by serious dis-
ease ?  648. What is the necessity of action to the nervous system ? 
AND  PHYSIOLOGY.
353
 requires sound sleep.   For this alone can return to the brain
 its expended  energies.   It is as  necessary to the brain  as
 steam to the locomotive.    And no person  can enjoy the  per-
 fection of health to old age, who does not gain a due supply
 of sleep.  Hence the very ambitious student, or the man eager
 to  make  money, whose  time, energies and thoughts  are  so
 engrossed that he can not, or will not, find time to sleep,  vio-
 lates  one  of nature's principal laws, and sooner or later  will
 receive the penalty.   And, according to  insane hospital re-
 ports, one of the principal causes of insanity is put down  to a
 want of sleep.

   645. Needs  Rest and  Recreation.—4. The mind not only
 needs sleep, but  also recreation or an occasional change of its
 objects of thought.   Long-continued trains of thought are  to
 the brain'what working one set of muscles incessantly all  day
 is to them—complete  exhaustion.  He  then that would  last
 the longest, must occasionally turn his thoughts from his or-
 dinary avocation completely, and so give the brain rest.  This
 applies to every one, whether  he  is the business man, student,
 or  the hard-working  farmer  or  mechanic.   And  every  one
 also needs a vacation,  or  at least  some change of employment,
 once or twice during the  year, when,  for a few weeks or days,
 he may break up the ordinary routine of life.
   646. Necessity of various Objects for  the  Mind  to di-
 vert  itself with.—5. If change or recreation be  so  impor-
 tant for the health,  how necessary that the  mind should have
 various objects on which to employ itself when free  from daily
 duties.   How  pleasantly,  and  profitably,  for instance,  can
 one  pass his  leisure hours, if he will but  cultivate  a taste
for music, reading, or some branch of natural history, as for
example zoology, botany,   mineralogy, or geology!    These
pursuits not only give healthful physical recreation,  but by

  614. What is the effect of a want or scarcity of sleep ? What is often a prominent
cause of insanity ? 645. What kind of rest does the mind need besides sleep ? Do all
employments need a vacation ? 646. Is exercise, that is taken simply for exercise, ever
iw best? What studies combine profit as well as recreation and exercise? 
354           HITCHCOCK'S  ANATOMY

the attractive and  fascinating  objects of study which they
offer, they divert the mind from the ordinary cares and trou-
bles of life, and also exert a healthful moral influence.   To
literary and  professional  men,  as well as many  of business
engagements, such a source of  recreation and improvement is
of very great importance, since often they are not interested
in many of the  recreations  and  pleasures  which divert  the
great mass of society,  and also  because new  thoughts and
means of illustration may be gained  from them.

   647.  The Brain  must be worked Philosophically, not
Spasmodically.— 6. The brain and nervous system will per-
form more labor, if worked philosophically, than if worked
spasmodically.  That is, mental and corporeal labor performed
regularly and steadily, and  only up to the ordinary power of
the brain and nerves to sustain, will not wear away the ner-
vous system to  such an extent as if it be performed  by over-
working for a few days and then lying idle.

   648.  Value of Mental  Abstraction —7.  As  a general fact
the mind acting through the brain can not successfully work in
the midst of  noise and external attractions.    But by  practice
many can engage in deep study and intense  thought,  even in
the company of those who are talking,  laughing, singing, or
in the midst of any noise.   This is a valuable acquisition and
one that should be  sought after by every one, since all of us
are liable  to be thrown into  such  circumstances,  that  we
must work, think, and transact business in  noise and confu-
sion.

   649.  The best Time  for  Study.—8. We see from this sub
ject that the  best time for study is in the morning, for then the
Ijrain is rested, and can with the  greatest vigor and  alacrity
engage  in its efforts.  But here the  fact presents itsolf, that
the morning is  the best time for physical  exercise,  and to
 647. How should the brain and nervous system be worked ? 643. Wuat is said «f \ha
value of mental abstraction ? 649. What is the best time for study i 
AND  PHYSIOLOGY.
355
which shall we give the  preference ?   Shall we deprive our
bodies of exercise, or shall we give up the  best efforts of the
brain ?   Without hesitancy, as a general  riC.e, we should
say, attend to  the physical exercise  first, for if the general
health be broken down, tho brain  will sympathize,  and then
close mental effort will be at an end.  Hence, although morn-
ing is the best time for study, yet we must not take the whob
of it for that purpose,  but must share  it with exercise.   To i
student who is passing through  a long course of study, early
rising  and retiring,  and generally exercise in the  morning
before commencing study, will tend to preserve and invigorate
health.  Studying  late  at  night  and  sleeping  long  in the
morning, are injurious to no class  of  people  more than to the
hard student.
   650. Pernicious  Effect of Tobacco   on  the Brain—9.
 The effect of  tobacco  on the brain is  thus described, in  his
 medical lectures, by  Dr. Solly, an eminent physiologist and
 practical  physician:  "I  would  caution you,  as  students,
 from excesses  in the use  of tobacco and smoking, and I would
 advise you to disabuse your patients'  minds of the idea that
 it is harmless.   I have  had a large experience of  brain dis-
 ease, and  am  satisfied now that  smoking is a most noxious
 habit.   I  know of  no cause or agent that tends so much to
 brino- 0n functional disease, and  through this  in  the  end to
 lead t > clinic diseases of the brain,  as excessive use of  to-
 bacco.'
    651. Power of the Fcclin_s over the  Nervous  System.—
 10. It is  wonderful and interesting  to see what is  the power
 exerted by the feelings  and emotions upon the nervous sys-
 tem, and  through that upon the whole body.   Let the farm r
 feel that his severe labor is sure to bring  him in good crops
 and how happily doiM he  persevere  in his  severe toil  month
 after  month.   And  if  the merchant can only know that  his
   But how shall exercise and studv both be properly attended to ?  What is said of early
 rising?  650. How does tobacco affect the brain ? 651. What effect have the emotion*
 upon the physical system ? 
 35C)           HITCHCOCK'S  ANA T O M V

 gains are great,  bow incessantly will he work day and night,
 and yet consider his no hard life.   But if there be no encour-
 agement, no  prospect  of reward to the working-man in his
 employment,  what drudgery does it become !   Nay, how posi-
 tively injurious  to health and vigor of body and mind.
   652.  To the scholar, however, this principle is much  more
 important than to  him who labors only  with the muscles, since
 these organs can  be worked to a considerable extent with an
 unwilling mind; but to work a brain  already  depressed and
 discouraged is much more difficult, and sure to bring on grave
 disease.   When the spirits are  light and the mind  free, the
 memory can be more readily stored with facts and principles,
 and the reasoning  powers more  easily developed.   It is hence
 the duty of teachers to make study as pleasant and attractive
 as possible ;  it becomes those who select the location and con-
 struct the  buildings of colleges,  academies, and  school-houses,
 to have a reference to taste and  comfort in their plans,  so that
 physical inconvenience may not  render study irksome, and
 that the taste of the student may be improved  as much  as pos-
 sible by the construction and arrangements of these buildings.
   653.  Control of  the Nervous  System  by  Moral  and
 Religious Feelings.—11.  Finally, of all  the sources  and
 promoters  of  health, correct moral and  religious feelings  and
 principles are among the most  powerful.   The reaction of  a
 guilty conscience upon the  body, in obstructing the  functions
 and in bringing on  weakness  and p emature decay,  is well
 known.  Equally powerful in promoting health and  longevity
 is an approving  conscience.   A cheerful acquiescence in the
 divine will has  often done  more  to restore  the  invalid  and
 maintain good health against disease, than all medical reme-
 dies ; while pure and ennobling sentiments and religious hopes
 have sometimes  been more efficacious to prolong life on earth
-than all other hygienic prescriptions.
  652.  What effect has pleasurable feelings on the progress of the  scholar?  658. State
 the value of an approving conscience upon  all classes of society, as it simply lvspucts
 physical health. 
AND  PHYSIOLOGY.
355-
COMPARATIVE  NEUROLOGY.
   654. Among all the higher
mammals we are able to trace
nearly  all the  different  parts
of the nervous system as they
are exhibited and arranged in
man, though  many of  them
are considerably  modified.
   655.  Weight of Brains.—
The  relative  weight of  the
brain is greater in the smaller
animals.   Thus,  in the mouse
it  is said to be ^d the weight
of the body.   In the elephant
the  weight  of  the  brain is
                             Fig.
  Brain of Squirrel laid open. B, Cere-
brum.  D, Cerebellum.  C, Optic Lobes.
thai., Thalamus Opticus.  c, a,  Corpus
Striatum.
330.
 Upper and Under Surface of Brain of Rabbit.  A, B, D, as before,  ol, Olfactive Lobes.
op, Optic Nerve,  mo. Motor Oculi. cm, Corpora Mamillaria.  c, c, Crus Cerebri, pv,
Pons Varolii,  pa, Patheticus.  tri, Trifacial,  ab, Abducens.  fac, Facial,  au,  Audi-
tory,  tag., Vagus, s, Spinal Accessory,  hyp., Hypoglossal.
655. What is said of the size of brains? 
35?
HITCHCOCK'S  ANATOMY
 gi„th the weight of the  body; in the ox,  7}Bth; in the fox,
 2^-th;  while in man it is 4'ath the weight of the body.
   656.  Proportion  of  the  Width  of Brain  and  Spinal
 Cord in  Man and other Mammalia.—This,  as well as the
 comparison of cerebral mass and cerebral nerves, between man
 and other animals, is  interesting.   The breadth of the spinal
 marrow is, to that of the  breadth of the brain, in man, a_
 1:7;  in the  dog, as 1 : 2.
   657.  Cerebral Nerves.—"The cerebral nerves correspond
 to those of man.   The first pair,  however,  forms in  some de-
 gree an  exception, for though not absent in all the whale
 family, it is wanting in the dolphins.  In most mammals the
 olfactory nerves  are thick  and have a cavity in them.   The
 fifth pair of nerves is, in many mammals, of peculiar strength
 and thickness when compared with that  pair in inane'
   658.  Sympathetic System. — "The  nervous  system  of
 organic life -  the great sympathetic — is formed, as  far as in-
 vestigations indicate,  essentially as in mane'   It is situated
 mostly in the cavities  of the thorax and  abdomen, and  follows
 the  course of the blood vessels.
   659. Tentorium—The tentorium cerebelli, which in man
 is a  simple tough membrane that separates the cerebrum  from
 the cerebellum, is very delicate in some  animals, as the horse
 and  dolphin;  while in the cat it is supported  by a bony plate
 springing from the skull,  and is a very firm membrane.   Its
 use to  protect the brain in those  animals  whose movements
 are at times violent and sudden, and especially those that leap
 great distances.
  660.  Spinal Nerves.—The  Spinal  nerves also, in general
 appearance,  are  like those  in  man.   The  number of pairs
varies in different species, as might  be inferred from the dif-
fering number of their vertebrae.

 656.  State the proportion of the width of the brain and spinal cord.  65T  What is said
-»f the cerebral nerves of animals? 658.  What is said of the sympathetic system? 669
Wkat is said of the tentorium ?  C60. What of the spinal nerves of animals ? 
A N PJ>  PHYSIOLOGY.
359
  661.  Actual  Proportion  between  Cerebrum  and  Cere-
bellum.—According to  Cuvier,  the  proportion of the cere-
bellum  to the cerebrum, by weight,  in  the  baboon, is as
1:7; in the dog, 1:8;  in the sheep, 1:5;  and in the horse,
1:7.

  662.  Spinal Cord.—The  essential difference between tne
ipinal cord in man and the lower mammalia, is  its greater
length,  and a narrow canal which runs longitudinally through
the middle of it.
  663.  Nervous  System  of  Birds.—The  brain of birds is
characterized  by  the  smallness of the hemispheres, though
more  fully developed  than in                 331
reptiles  and  fishes.    In the
sparrow  the  weight   of the
brain to  the whole body is as
1: 25 ;  in  the goose,  1: 300 ;
and in the cassowary, 1:1000.
It is destitute of convolutions,
or in other  words is perfectly
smooth on its  surface,  and has
lar^e cavities or ventricles con-
tained in it:  and, as in mam-
mals, the  mass of the brain
is greater  than  that   of  the
spinal cord.   The pairs of the cerebral  nerves are the  same
as in mammals;  also the principal divisions  are the same.
The cerebellum, as in  man, exhibits the  arbor  vitse when cut
through vertically.
  664.  Nervous  System  of  Reptiles.—The brain of rep-
 Brain of Buzzard.  B,  Cerebrum. C,
Optic Ganglia. D, Cerebellum,  g, Pineal
Gland.
 661. What is the proportion between the weight of the cerebrum and cerebellum in
some of the lower animals?  662. What is the essential difference between the spinal cord
of man and that of most quadrupeds? 663. How is the brain of birds characterised?
Gire some of the proportional weights of it compared with that of the whole body J
                             16 
360
HITCHCOCK'S   A N A T OMY
           Fig. 332.              tiles constitutes but  a  very
                                small part of the  body.   In
                                the frog the proportion to the
                                whole weight of the  body is
                                as   1: 172;  in the Coluber
                                matrix (snake), 1 : 792 ; in a
                                turtle, 1 : 5688.   The hemi-
                                spheres are smooth and hollow
                                internally.   The  optic  lobes
                                are large in proportion to the
                                size of the eyes, and are hol-
                                low internally.   The cerebel-
                                lum of frogs i_ merely a thin
                                plate of nervous matter.
                                  665.  Nervous  System of
                                Fishes.—We find the  lowest
                                development of the nervous
                                system among vertebrates in
the fishes.   The  brain here does  not fill the whole  cranial
cavity, so  that  between  the brain  and  dura mater there is
found a quantity of loose cellular tissue, with which is inter-
spersed a fluid oil.  The brain in weight does not  equal that
of the spinal cord, nor is it but a little broader than the cord.
Its weight in proportion  to  that of the body is about yj'-ooth
part.   It  is composed of eight lobes,  partly  in  pairs,  and
partly unpaired behind one another, which seem to correspond
to the cerebellum (divided), corpora quadrigemina, thalami
optici, and medulla oblongata.
   666. Electrical Organs in Fishes.—There are at  least
seven species of fish that possess the power of givin^  electric
discharges.  The  organs which accomplish this in the Torpedo
are two  large crescent-like bodies (see  Fig. 334), Avhich are
 Brain of Turtle.  A, Olfactive Ganglia.
B, Cerebrum. C, Optic Ganglia. D, Cere-
bellum.
 664. What is said of the brain of reptiles?  State its comparative size with that of the
whole body.  665. State some of the peculiarities of the brain in fishes.  What is its
relative weight?  666. What is said of the electrical organs of some fishes?  Give the
anatomy of these organs. 
AND   PHYSIOLOGY.
361
Fig. 333.
  Brains of Fishes.  A, Olfactive Lobes or Ganglia.  B, Cerebral Hemispheres.  C, Op«
tic Lobes. D, Cerebellum,  ol, Olfactory Nerve,  op, Optic Nerve, pa, Patheticus.
rt'o, Motor Oculi. ab, Abducens.  tri, Trifacial, fa, Facial,  au, Auditory,  vag, Va-
g'.is.  It, Tubercles or Ganglia of the Trifacial,  to, Tubercles of the Vagus.


made up  of a  large  number of  short, six-sided prisms,  and

are  abundantly supplied  with  nerves.   And as  these organs

are made up of prisms,  which  stand  end  upon  end,  and  not

side by side only,  as they appear in the  cut, the idea seems 
36:2            HITCHCOCK'S   ANATOMY

            Fig. 334.                         Fig. 335.
  Electrical Apparatus of Torpedo,  b,      Nervous System of an Articulate.
Branchiae,  c,  Brain,  e, Electric Organ.
g. Cartilage of Cranium, me, Spinal Cord, n, Nerves to the Pectoral Fins, nl, Lat-
eral  Nerves to the Body, np, Large Nerves  (Pneumogastric) to the Electric Organ.
o, Eye.

plausible that  they may be  regarded  as Voltaic piles, or a
reservoir of  electric  power which  the fish  can discharge at
will.   And it  is necessary  for the generation of this electrical
discharge that  the integrity of the  nervous system be  main-
tained.

  667.  Nervous System  in  Articulata.—In the Crusta-
ceans the nervous system consists of ganglia and cords.  The
central ganglion may be regarded  as a brain, which sends  off
nerves of vision, audition, feeling,  and  smelling.  A splanch-
nic or sympathetic nerve is also found, as in the Arachnoidea
and Annelida.   The  two latter classes  have  ganglia,  which
667. State the general plan of the nervous system in articulates. 
AND  PHYSIOLOGY.
363
 may be  called  a brain.   In
 Insects  " the central  parts
 of the  nervous  system  con-
 sist  of a  brain and a  ven-
 tral  cord,"  as  is  shown on
 Fig. 336.    In  some of  the
 ,lower  tribes  of  Articulates,
 as the  Helminthes  and Rota-
 toria,  the  nervous   system
 is feebly and indistinctly de-
 veloped.

   668.  R e f 1 e x A c t i o n s i n A r-        Nervous System of a Beetle.
 ticulates. —This  sub-king-
 dom is  remarkable for its  reflex actions.  Thus if the head of a
 centipede be cut off while  it is in motion,  the body will con-
 tinue to move by the  action  of its legs;  and the same will
 take place,  if the body is  divided into several segments.   The
 explanation is as  follows.   "The body is moved forward by
 the regular and successive action of its legs, as in the  natural
 state : but  its movements are  always forwards,  never back-
 wards, and  are only directed to one side,  when the forward
 movement is checked  by an  interposed obstacle.   Hence,  al-
 though  they might seem to indicate consciousness and  a guid-
 ing will, they do  not so in reality : for they are carried on as
 it were  mechanically, and show  no direction or object,  no
 avoidance of danger.   If  the body be opposed in its progress
 by an object of not  more than  half its height, it mounts over
 it, and moves directly onwards, as in its natural state : but if
 the obstacle be equal to  its own  height, its  progress is  ar-
 rested, and  the cut extremity of  the body remains forced up
against  the opposing  substance, the  legs still  continuing to
moveP
 What is the name of the principal ganglia?  668. What is saiu of the reflex actions
of articulate animals?  What are these reflex actions sometimes mistaken for'  Giv«
the example.
FiG. 336.
 
364
HITCHCOCK'S  ANATOMY
  669.  Nervous   System  of  Molluscs.—Cephalic  Gang-
]ia.— Pedal    Ganglia. —Parieto - Splanchnic   Ganglia.
—In roost  of the Molluscs  the nervous  system  is  well de-
                             FiG. 337.
                              A
  TffeT-ous System of Argonauta Argo.  A, As seen in front.  B,  As viewed in profile;
•howing the relations of the Nervous Centers to the Buccal Mass.  a, The Esophagus b,
and the Eye c. a, Cephalic Ganglion,  b, Buccal Ganglion,  c, Sub-Esophageal Gang-
lion,  d, d,  Stellate Ganglia of the Mantle,  e. Visceral Ganglion. /, Nerves of the
Arms, with  Ganglionic Enlargements,  g, Optic  Nerves,  h, h, Eyes,  i, i,  Branchial
Nerves with their Ganglia. 
AND PHYSIOLOGY.
365
veloped;  the most  so in  the Cephalopoda,  which are the
highest in organization.   In these we find a central organ
quite like a brain,  enveloped by a membrane analogous  to
the Dura Mater.   This system  is shown on Fig. 337.   The
general arrangement is that of three principal pairs of ganglia
with nerves  proceeding from them.   The  first pair is called
the Cephalic ganglia,  which  is  the  largest, and is located
above or on the sides of the esophagus, with a collar of nerves
surrounding  that tube.  This gives off nerves  to the organs
of vision and taste, and to the muscular apparatus of the mouth.
The second pair, called the Pedal ganglia,  is located beneath
the esophagus, giving off" nerves to the foot and the organs of
hearing, when this  sense  is not  actually located in  the  foot.
The third pair, the Parieto-Splanchnic ganglia,  are usually
found in  the posterior part of the body giving nerves to the
muscular and sensitive walls of the body, the respiratory ap-
paratus, the  heart and large blood vessels.
   670.  Nervous System of Radiates.—Need  of  a Nerv-
ous System.—Among the higher Radiates a nervous system
of inferior organization can be found.  For the most part it
consists of a ring of nervous
matter   about  the   mouth,
which sends off branches  in
different   directions.    "  In
Medusae  the nervous system
consists of a simple cord,  of
a string of ovate cells, form-
ing a ring aroung the lower
margin  of  the  animal."—  Nervous Sy8tem of star.Fish. „,-,Live
Agassiz.  (Fig. 338.)  Gang-  Ganglia.
lia, or reservoirs of force can but seldom be found.
   671.  Among  the Infusoria no nervous  system can be de-
tected,  and if any exist, its participation in the general course
  663 What is the principal arrangement of the nervous system among molluscs? 670.
What is the nervous system of the radiates? 671. How is the nervous system  amons
 iaditWH
 
866            HITCHCOCK'S  ANATOMY

of vital action must be very trifling.   For the  simplest office
of a nervous system is to establish a communication between
the different parts of the body; but if every part of the body
has similar endowments,  there  can be no object in  such com-
munication.  For instance, where every part  of the surface—■
as is the case in those animals—is equally susceptible of ab-
sorption, there can be no need of a circulating  system,  and
where  contractility seems to be diffused through the body
alike, a nervous system would be superfluous.
871. What of the nervous »y»tem of Inf-torta. 
    CHAPTER    EIGHTH.

THE INLETS TO THE  SOUL.—THE SENSES,
GENERAL  REMARKS,
  672.  The  Senses.—Dependent on  the Mind.—These  are
commonly known under the name of senses.  Five are usually
reckoned, Seeing,  Hearing, Tasting, Feeling,  and Smelling;
and it is by these alone that we are made acquainted with ex-
ternal objects.   In other words, sensation  may be defined as
the consciousness  of impressions.  The  mind, for aught we
know, might be able to  carry on its  functions of  thinking,
reasoning, and memory, and also be conscious of its own ex-
istence,  if it  were deprived of the  senses:  but it could not
make itself felt on other minds, nor increase in knowledge and
discipline without their aid.   And although the primary ob-
ject of  the senses  is to promote physical  enjoyment,  yet their
highest  and  noblest use  is to  subserve  the purposes of the
mind.
   673.  Senses  best  Developed  in  Lower  Animals.—In
man the*senses are not so  fully developed  as in  most of the
lower animals.   But this deficiency is much more than  com-
pensated by the superiority of his intellect.
   674.  Effect of excessive  Use of the Senses.—Excessive
indulgence of any of the senses is apt  to produce  painful in-
stead°of pleasurable  sensations.   Thus  heat of  a  moderate
  072. What are the inlets of the soul ? Is mind necessary for the existence of sense ?
What is the primary use of the senses?  What should be^their highest use?  67  In
what animals are  the senses the most perfectly developed?  674. How does excess.v.
indulgence affect the senses? 
36S
HITCHCOCK'S   ANATOMY
 temperature is  always  agreeable, but painful if  much in-
 creased.   Many odors snuffed  in  small quantity are pleasant,
 but when given to satiety, become disgusting.  The probable
 design of this provision seems  to  be  to prevent injury  by an
 inordinate stimulation of any of the nerves.  For instances are
 on record, where  the mucous membrane of the  nostrils has
 been  severely  affected by  the fumes  of ammonia given in
 fainting.
   675.  Habit  makes  painful  Sensations  pleasant, —It
 is a curious but interesting  fact that the pain excited by un-
 accustomed  sensations  may sometimes be exchanged  for  its
 opposite,  after the system  has become  habituated to  them.
 Thus tobacco and  alcohobc liquors are  at first disagreeable to
 most  persons;  but when the disgust has been overcome by
 any means a love  for them  succeeds, and generally a strong
 craving for excessive  indulgence also.
  676. Nerves  of Special  Sense  can  perform   but  one
 Fu net ion.—The nerves of  special sense are incapable of per-
 forming  any function except  that for which they were orig-
 inally designed.    Thus the  optic nerve can perform  the func-
 tion  of vision only, the olfactory only that of smelling, and
 the auditory only  that of hearing.

  677.  Effect  of Belief on  our Sensations.—The  effect
 of previous  belief  in  modifying our  sensations, is  shown  in
 the two cases  copied from Carpenter's  Physiology.    "A
 clergyman told me that some time ago  suspicions  weie" enter-
 tained  in his  parish,  of a woman  who was supposed to have
poisoned her newly born infant.   The coffin was  exhumed.
and the procurator fiscal,  who attended with the medical men
to examine the  body,  declared  that he  already perceived  tha
odor of decomposition, which made him  feel faint, and in con-
sequence  he withdrew.   But  on  opening the  coffin, it was

  What instance of this from odors? 675. How does habit sometimes affect painful sen-
 sations?  What examples? 676. What is said of the function  of tho nerves of special
 wnse? 677. How does our belief affect our sensations?  Give the instance of the infant 
AND  PHYSIOLOGY.
369
found to be empty; and it was afterwards ascertained that no
child  had been born,  and consequently no murder committed.
The  second  case  is  yet more remarkable.   A  butcher  was
brought into the shop  of  Mr. McFarlan, the druggist, from
the market place opposite,  laboring under a terrible accident.
The man on trying to hook up a heavy piece of meat above
his head, slipped, and the  sharp  hook penetrated his arm, so
that he himself was suspended.   On  being  examined, he was
pale, almost pulseless, and expressed  himself  as suffering the
acutest agony.  The arm could not be moved without causing
excessive  pain; and in cutting off the sleeve, he frequently
cried out: yet when the arm was exposed, it was found to be
quite uninjured, the hook having only traversed the sleeve of
his coat! !"
              THE  SENSE  OF  VISION.

         DEFINITIONS  AND  DESCRIPTIONS.

  678.  The chief organ of this sense  is the eye, although its
appendages perform very important secondary functions.
  679.  Anatomy of the Eye.—The  human  eye is  nearly
globular in form, with a diameter a little less  than one inch,
the lateral diameter being one  twentieth of an inch less than
the anteroposterior.   (Fig. 339, p.  370.)   In general struc-
ture it  is made up of three membranes, and  three humors,
or transparent media, and is  covered on the surface exposed
to the air by mucous membrane, which also lines  the inside
of the lid,  so that the two surfaces at some points are always
in contact.
  680.  Sclerotica.—The membrane which covers the larger
portion  of the  eye is called  the Sclerotica,  from the Greek

 Give the instance of the butcher. 67S. What is the chief organ of sight? 679. What
is the shape of the eye?  Its diameter ?  Of how many media and membranes is it
made up? 
370
HITCHCOCK'S  ANATOM-
Fig.  339.
  Longitudinal Section of the Globe  of the Eye. 1, Sclerotic, thicker behind than ia
front. 2, Cornea, received within Anterior Margin of Sclerotic, and connected with it by
means of a beveled edge.  3, Choroid, connected  anteriorly with (4,) Ciliary ligament,
and (5,) Ciliary Processes.  6, Iris.  7. Pupil.  8, Third Liyer of Eye, Retina terminating
anteriorly by abrupt border at commencement of Ciliary Processes.  9, Canal of Petit,
encircles the Lens (12); the thin layer in front of this canal is the Zonula Ciliaris, a pro-
longation of Vascular Layer of Retina to the Lens.  10, Anterior Chamber of Eye con-
taining  Aqueous Humor; the  lininsj membrane, by which  the humor is  secreted, is
represented in diagram.  11, Posterior Chamber.  12, Lens, more convex behind than
before, enclosed in its proper Capsule.  13, Vitreous Humor enclosed  in Hyaloid Mem-
brane, and in cells formed in its interior by that membrane.  14, Tubular Sheath of
Hyaloid Membrane, which serves for the passage of the Artery of Capsule of the Lens.
15, Neurilemma of Optic Nerve. 16,  Arteria Centralis Retime, embedded in the center.


signifying hard, because it is a firm and stout membrane.  Its

color  is nearly white, covering the posterior four  fifths of the

eye, it is commonly called the white of the eye, and is  thickest

in its  posterior parts.

   681.  Cornea.—The  external  covering  of  the front  fifth

part of the  eye is  called  the Cornea,  from the Latin  word

meaning horn-like, and in  two respects it bears the same rela-

tion to the ball  of  the  eye,  as the crystal does to the watch,

since it  is fitted into the sclerotic  by a  beveled edge, as  is a

watch-glass,  and also because it is perfectly  transparent.   Tho

blood-vessels of this membrane are among the smallest in  the

body,  being  too small  to  allow  the passage of the blood-cor-

puscles, and only convey the plasma or serum.

  680. Describe the sclerotic coat. 681.  What is the cornea?  To what may  it \e com
pared in the watch ? 
AND   PHYSIOLOGY.
371
Fig. 340.
   682.  Choroid  Coat.—Iris.
— Ciliary   Processes.—The
middle   coat  of  the eye  is
made  up  of  three  portions,
the  Choroid  membrane,  the
Iris,  and   the   Ciliary  pro-
cesses.    The first, Choroid, is
named  from the fact that it is
entirely  made up  of blood-
vessels,  of a chocolate-brown
color on  the  outside, and  a
deep black on the inside.   It
covers the posterior four fifths
of the  eye,  and corresponds
to the  sclerotic  coat outside
ofit.  The Iris, so called from
the diversity  of  color which
  Plan of the Structures in the Fore Part of the Eye, seen in Section. 1, Conjunctiva.
2, Sclerotica. 3, Cornea.  4, Choroid.  5, Annulus Alhidus;  before this is is seen the
Canal of Fontana.  6, Ciliary Processes.  7, Iris.  8, Retina.  9, Hyaloid Membrane. 10,
Canal of Petit (made too large). 11, Membrane of the Aqueous Humor (too thick^)  a,
Aqueous Humor; Anterior Chamber, and (a,) Posterior Chamber, b, Crystalline Lens.
c, Vitreous Humor.
                              Fig. 341.
  Choroid Coat of the Eye.  1, Curved lines marking the arrangement of Vena? Vortl
C0S83. 2, 2, Ciliary Nerves.  3, A long Ciliary Artery and Nerve.  4, Ciliary Ligament.
5, Iris.  6, Pupil.
  682. Of what three portions is the choroid coat composed ?  Giv« their names.  De-
scribe the Ins. 
372           HITCHCOCK'S  ANATOMY

it  presents in different  persons—and  it  is the  color of this
which we mean when we speak of the color  of the eye—cor-
responds in position to the cornea lying immediately under it.
FiG. 342.                         Fig. 343.
External View of the Iris.           Anterior Segment of a Transverse Section
                            of the Globe of the Eye seen from within.
   1, Divided edge of the three Tunics ; Sclerotic, Choroid (the dark layer), and
   Retina. 2, Pupil.  3, Iris, the surface presented to view in this section being
   the Uvea.  4, Ciliary Processes.  5, Scalloped Anterior Border of tho Retina
It is circular in form,  containing a  few muscular fibers, with
a circular opening through its center, from one  third to one
twentieth of an inch in diameter, which is known as the pupil.
The Ciliary processes  are  minute triangular folds of the Cho-
roid co.it,  which lie upon the interior surface of the iris, with
their bases directed toward  the  pupil.    They  are about sixty
in number, and are  divided into large  and  small,  the latter
being  placed between the former.   The  Pigmentum Nigrum,
or black paint,   is au extremely  tenuous membrane,  which
lines the inside of the  choroid coat.   It is of a jet black color,
and is easily destroyed merely by allowing a stream of water
to fall upon it.
   683.  Retina.—The inner membrane of the eye  is the Re-
tina, which is merely  an expansion of the optic  nerve, upon

  What is the diameter  of the  iris?  What are the ciliary processes? How many are
there? What is the pigmentum nigrum ? 683. Describe the retina. 
AND   PHYSIOLOGY.
373
the inner side of a hollow sphere, formed by the membranes
already mentioned.

   684.  Microscopic  Structure  of  these   Membranes.—
The structure of these membranes, as revealed by the micro-
scope, is very complex.  The Cornea is made up of four sim-
ple membranes,  the Choroid of three, and the Retina of four


                            Fig.  344.
 Vertical Section of the Human Retina and Hyaloid Membrane h, Hyaloid Membrane.
%', Nuclei on its inner surface, c, Layer of Transparent Cells, connecting the Hyaloid
and Retina,  c', Separate Cell enlarged by imbibition of water,  n, Gray Nervous Layer,
with its Capillaries.  1,  Its Fibrous Lamina. 2, Its Vesicular Lamina.  V, Shred of Fi-
brous lamina detached.  2', Vesicle and Nucleus detached,  g. Granular Layer. 3, Light
Lamina frequently seen,  g', Detached Nucleated Particle of the Granular Layer, m, Ja-
cob's Membrane, m', Appearance of its Particles, when detached,  m", Its Outer Sur-
face.—Magnified 320 diameters.


The Sclerotic is  for the most  part made  up of  white  fibrous

tissue, and a large portion of the Choroid coat is composed of

blood-vessels, although the inner membrane—the Pigmentum

Nigrum or black paint—consists of minute  six-sided cells  re-

sembling a tesselated pavement.   The Retina is for the most

part made up of  the different  forms of nervous  tissue  and its

membranes.

 6S4. Give the microscopic structure of the cornea.  Of the choroid, the pigment, and
the retina. 
374
HITCHCOCK'S   ANATOMY
   685.  Humors  of the  Eye;  Aqueous.—Of the three Hu-
mors or liquid substances composing the eye, the Aqueous or
watery is situated in the anterior portion of this organ behind
the cornea, and in  front  of the crystalline  humor soon to be
described.   It is  a  liquid like water, with an alkaline taste,
and only a few drops in quantity.   The Iris is placed directly
in the middle of this fluid.

   686.  The   Lens.—The  Crystalline Lens  or  Humor  (so
called because it refracts light and  is transparent like a crys-
tal)  is a double  convex  lens, the  posterior convexity being

          Fig. 345.                          Fig. 346.
  Front View of the Crystalline Lens.      Side View of the Lens. 1, Anterior Fac«.
                               2, Posterior Face.  3, Circumference.

 greater than  the anterior, and is  located directly behind the
 pupil, so that all the  light which  enters  the eye, must pass
 through this  and be refracted.   This lens is  made up of con-
 centric layers like an  onion, and also of  three triangular seg-
 ments, with  their sharp edges directed  towards the center,
 both of which structures, by  boiling  the  lens in water for a
 short  time, can be  readily seen.   Fig.  347 represents  the
                                      difference   in  diameters
               FlG- 347-                of  the  lens at different
                                      periods of life,   a, rep-
                                      resents it at birth, b, at
                                      six years  of age,  c, its
 n  . „-   r       .  .         w*ss»     appearance in an adult.
 Crystalline Lens,  a, At birth,  b, At six years    j                    '
old.  c, Aduit.  d, Altered by alcohol.           and d,  after it has been
 685. How many humors are there in the eye? Describe the aqueous.  686. What h
the crystalhne ku_K„ ? What kind <rfa leas is it? Of how many selects is it made up J 
AND  PHYSIOLOGY.
375
hardened and partially divided into segments by an immersion
in alcohol.
   687.  Vitreous.—The  Vitreous  Humor (from its resem-
blance to glass)  is  of the form of a sphere, with the  anterior
portion removed, and constitutes seven eighths of the  globe of
the eye.   It is a transparent  fluid enclosed in a transparent
membrane, and through its central portion from the entrance
of the  optic nerve, there passes a  small artery  to the  lens,
which supplies it with blood.
   688.  Lachrymal Gland.—Nasal  Duct.—At the outer angle
of each eye is found a gland called the Lachrymal gland, nearly
three fourths  of an  inch in  length, and of a flattened oval

                           Fig.  348.
  Posterior View of the Eyelids and Lachrymal Gland.  1, 1, Orbicularis Palbebrarum
Muscle.  2, Borders of the Lids. 3, Lachrymal Gland.  4, Its Ducts opening in the Up-
per Lid.  5, Conjunctiva covering the Lids. 6, Puncta Lachrymalia.  7, Lachrymal Ca-
runcle as seen from behind.

3hape.  (Fig. 348.)  Passing from this gland to the eye, are from
eight to twelve small  ducts, which open upon the under side
of the  lid near its  edge, about one twentieth of an inch apart,
which  carry the tears  to the eye.   By continual winking this

 687. From what does the vitreous humor get its name? Describe it. 688. Where are
the lachrymal glands situated?  What is their size ? How many dncts have they ? What
do they secrete ? Of what use is winking? 
376
HITCHCOCK'S   ANATOMY
            Fig. 349.              fluid is uniformly distributed
                                 over the  whole ball of  the
                                 eye, aad the excess  is carried
                                 away  from the eye  by  the
                                 two lachrymal canals, which
                                 commence  at the  two little
                                 projections  near  the  inner
                                 angle of each lid of the eyo,
                                 appearing like minute  black
                                 specks. Both of these very soon
                                 unite into a larger tube called
                                 the  nasal  duct,  (Fig. 349,)
                                 which descends  inwardly and
                                 empties itself upon the nostrils.
                                    689.  Eyebrows.—The
                                 Eyebrows   are   projecting
                                 arches  of fat and  skin, cov-
                                 ered with  short and  thick
                                       hairs which encircle the
                                       upper portion  of  the
                                       eye.  They are provided
                                       with  muscles,   so  that
                                       they  can   be  made  to
                                       shade the  eye  more  or
                                       less   perfectly,  as  ne-
                                       cessity may require.
                                         690.  Eyelids___The
                                       Eyelids    are   movable
                                       membranous  and mus-
                                       cular  coverings which
                                       are placed directly  up-
                                       on the eyeball, and are
designed for protective organs against mechanical violence and
too powerful light.   Their free edges are  called  Tarsal Carti-
  Where are the lachrymal canals and what do  they carry?  What is the nasal duct?
6-W. Describe the eyebrows. 690. What are the eyelids? What are their edges made up
of?  What glands directly in them ?
 Lachrymal Canals. 1, Puncta Lachry-
m.ilia.  2, Cul-de-Sac at the Orbital End
of the Canal. 3, Course of each Canal to
the Saccus Lacrymalis. 4, 5, Saccus La-
crymalis.  6, Lower Part of the Ductus
ad Nasum.
Fig. 350.
 Front View of the Left Eye—moderately opened.
I, Supercilia.  2, Cilia of each Eyelid.  8, Inferior
Palpebra.  4, Internal Canthus. 5, External Can-
thus.  6, Caruncula lacrymalis. 7, Plica Semilu-
naiis.  S, Eyeball.  9, Pupil. 
AND  PHYSIOLOGY.
3 i i
lages,  directly  in  the  substance  of  which  is  placed a  large
quantity of minute glands, called Meibomian Glands.
            Fig. 351.
Fig. 352.
  Meibomian Gland highly
magnified.
    Meibomian Glands seen from the Inner or Ocu-
  lar Surface of the Eyelids,  with the Lachrymal
  Gland—of the Right Side, a, Palpebral  Conjunc-
  tiva.  1, Lachrymal Gland.  2, Openings of Lachry-
  mal Ducts.  3, Lachrymal Puncta.  6, Meibomian
  Glands.


   691.   Muscles  of   the  Eye.—The

 Ball of the eye is moved by six distinct

 muscles,  four  straight  and two oblique

 muscles,  as is shown in the cut.  Their

 names are Rectus  Superior and Inferior, External and Inter-

 nal, and  Superior  and Inferior Oblique.
  Muscles of the Eyeball.  1, A small                  Fig. 353,
 Fragment of the  Sphenoid Bone
 around entrance of Optic Nerve into
 Orbit. 2, Optic Nerve. 3, Globe of
 Eye. 4, Levator Palpebrae Muscle.
 5, Superior Oblique Muscle.  6. Its
 Cartilaginous Pulley. 7, Its reflected
 Tendon.  8, Inferior Oblique Muscle;
 the small square knob at its com-
 mencement is a piece of its bony
 origin broken off.  9, Superior Rec-
 tus.  10, Internal Eectus almost con-
cealed by Optic Nerve.  11, Part of External Rectus, showing its two heads
12, Extremity of External Rectus, at its Insertion;  the intermediate portion
having been removed.   13, Inferior Rectus.  14, Tunica Albuginea formed by
of tendons of four recti.
of origin.
of muscle
expansion
691. How many muscles for moving the eyeball ?  Give their names. 
378
HITCHCOCK'S  ANATOMY
            FUNCTIONS  OF  THE  EYE.

  692.  The primary and obvious use of the eye is to receive
the form and color of different objects, and  to  transmit them
to the brain.
  693.  Use of the  Coats—Sclerotica—Cornea —Choroid —
Hack  Paint—Iris—Ciliary Processes—The  Retina—The
use of the firm and hard sclerotic coat is to give a firm attach-
ment to the muscles which move the eye, and also secure pro-
tection to the delicate parts within.   The cornea is tough but
transparent, so that the anterior portion of the eye  may be
firm and at the same time admit the rays of light.   The cho-
roid coat furnishes the blood to the  eye, it being for the most
part entirely made up of blood-vessels.   It also secretes the
black paint (Fig. 288), which  is of great service  in  absorb-
ing the superfluous or wandering rays of light which otherwise
would obscure the image on the retina.   A similar provision
is made by painting black  the  tube of  the  telescope and mi-
croscope.   The iris  regulates the amount of light entering the
ball, by its contraction and expansion.   This  function is per-
formed by  the  radiated  and  circular  muscular fibers,  the
latter  of which  contract  by the stimulus  of strong  light:
but  if the  light  be  feeble, the radiated  contract,  and  thus
enlarge  the pupil.   The  retina, with  the .vitreous  humor
in  front  and  the black  paint directly  behind it,  receives
the image  of  the object  before the eye.   It bears the same
relation to the  other  parts of the eye as the silvered or glass
plate does in the  camera of the photographist.  This  impres-
sion is carried to the brain by means of the optic nerve.
  694. Use of  Hie Humors —Aqueous —The Lens —Vitreous
—Of the three humors or media of the eye,  the aqueous is
the least important, since  if by accident or operation it  is re-
  692. State the use of the eye.  693. Give the use of the sclerotic coat.  Of the cornea,
What does the choroid furnish to the eye ? Of what service is the black paint ? Wha'
does the iris do ? What is the function of the ciliary processes ?  What is the use of tht
retina ? 694. Which is the least important of the humors ? 
AND  PHYSIOLOGY.
37(J
moved, nature will  soon replace it; but  this is true of no
other medium.  The aqueous humor, however, is of great use
to keep the front parts of the  eye in a soft and elastic  condi-
tion,  and also to furnish a medium in which the iris  may
readily be contracted and relaxed.  It also aids in properly
refracting the rays of light, so that the most perfect  image
may be formed on the retina.   The use of the crystalline lee 3
is also to refract the rays of light, so that an image of suffi-
ciently small  size  may be formed on the retina.   Otherwise,
when we look at any object larger  than  the  diameter  of the
pupil, we should  be unable  to see it,  only by successively
looking at  minute portions of it.   The vitreous humor assists
in the same refraction of the rays,  and incidentally subserves
the purpose of fixing at a proper  distance the lens, so that the
image may be formed exactly at that point on the retina called
the focus, where it will be the most distinct.
   695.  Need  of Three Media—But what is  the necessity for
three media of refraction, and  why  will not the crystalline lens
answer the whole  purpose ?   This is owing to  some  of the
properties  of light.   Light is composed of seven rays or colors,
some of which are more easily refracted  than others ; that is.
some rays  are bent  farther from a perpendicular to the sur-
face than others.   Hence, upon the edges of an image  formed
by a single lens, every part of which  is of the same density,
we should  see several of the prismatic colors, which would give
an indistinct  image.   In the telescope  and microscope this
difficulty is remedied  by forming  a lens of crown  and flint
glass, one  of which  has a stronger dispersive  or refractive
power than the other.   In the eye the same error  is obviated
by means of the crystalline lens, which has a greater  refrac-
tive power  than the vitreous  humor, and consequently, when
the ray  is too much refracted by the crystalline lens,  a com-

  itate the use of the aqueous.  The use of the lens. What does the vitreous humor aid
in * ' 695  What is the need of three humors ?  How many distinct colors does light con-
sist of ? What similar purpose do lenses of  different densities answer in telesoop»s>
 Which of the three humors has tha greatest refractive power? 
380
HITCHCOCK'S  ANATOMY
pensation is effected by the vitreous humor, which refracts les3
than the lens.
  696.  The  Secretion of the Lachrymal Glands.—The lach-
rymal gland  is designed to secrete a saltish fluid known as the
Tears.   This is of great service in  lubricating and  keeping
moist the surface of the eyeball, so that it may move readily
in its socket, and also to keep the cornea from becoming hard
and dim.   The tears also moisten the back part of the nostrils,
and are ultimately poured into the  pharynx.   The amount of
tears  which  is  daily secreted  is  estimated at four  ounces,
and it is greatly increased by strong  emotions, whether pleas-
ant or sorrowful, as  it is well known that  a person i3 apt to
cry when very sad or very happy.
  697.  Service of  the  Eyelids—Necessity  of Constantly
Winking—Eyelashes.—The eyelids are of service  to keep
the light from the eyes when it is too intense, or when it  is
necessary to  exclude it  entirely, as  during sleep.    Another
valuable service which  they perform is  to spread the  tears
constantly and uniformly over  the eyeball.  This is the rea-
son why we are constantly but unconsciously winking during
every few seconds of our waking hours.   The eyelashes which
line the  edges of  the lids, prevent the perspiration which  is
secreted on the lids  from entering the eye,  and thus irritating
it, since by the law  of capillary attraction  the  tears will run
towards the free extremity of the hair, where they will  accu-
mulate to such a size that they drop off.   The eyelashes also
prevent, in some degree, dust from entering the eye.
  698.  Use  of the  Eyebrows.—The  eyebrows  perform  a
similar office to the  eyelids, though  not so important.   The
hairs which cover them, like the lashes, convey away the per-
spiration from the forehead, and allow it to fall in front of the
eye, and not directly upon the ball; while, by means of the

  696. What is the secretion of the lachrymal gland? What is the use of the tears?
What quantity of tears are secreted daily? 697. Of what service are the eyelids? Why
do we constantly wink?  Of what service are the eyelashes? 698.  What service do the
eyebrows perforin? 
AND  PHYSIOLOGY.
381
  muscles attached to  the  integuments, whenever it is desired
  they bring the brows in front of and  above the eye in such a
  manner as to afford it a very considerable protection from ex-
  cessive light.
    699.  Short  and  Long  Sightedncss—The  phenomena  of
  short and long-sightedness are worthy  of a passing notice.
  Short-sightedness results where the lens of the  eye has too
  much convexity, which causes the image to be formed in front
  of the retina.  In such persons the eye generally has greater
  prominence than in  others.   But  persons thus affected will
  probably in later years have  better  eye-sight than if short-
  sightedness had not existed.   A too much flattened  state of
  the lens occurs in those who are long-sighted.   This is gener-
  ally the case with those somewhat advanced in life.  In this
  case the distinct image will be formed behind the retina, and
  it requires a convex lens, in the form of spectacles, to correct
  the error.
    700.  Other  Interesting  Phenomena  of  Vision.—A few
  other phenomena connected with the function  of vision de-
  serve attention.  One  is  the fact, that although we have two
  eyes  and two  distinct images are  transmitted  to  the  brain,
  yet but one object is  seen.  And if we  look at an object with
  only one eye, we see the image nearly as distinct as with both
  eyes.   Another is, that although the image  on  the retina  is
  inverted,  yet to the mind it appears in its true position.  For,
  since the  rays  of light pass through the lens in nearly straight
  lines, the  ray coming, for instance, from the top of a tree, will
  fall upon the lowest part of the retina,  while  the  ray coming
.  from the bottom will  strike  the upper part, and hence the
  image will be inverted, although to the " mind's eye"  it will
  be erect.   Another  fact is equally  wonderful.  We  are able
  to see with distinctness an object only a few inches from our
 699. What is the cause of short-sightedness?  What is the reason of long-sig:
What kind of a lens is required for long-sighted people, and why ?  700. Whs
facts connected with the physiology o. vision ? 
3 R_           HITCHCOCK'S   ANATOMY

eyes,  and almost instantly, by  turning them  to a mountain
top several miles distant, we can see an object there with per-
fect cleaarness.   No optical instrument  can be made which
will so  quickly do  this,  for it is necessary to make a new ad-
justment of the lenses  to adapt it to different distances, but
the eye is at once ready.   It is  supposed that this  adjustment
is effected by a shortening or lengthening of the diameter of
the crystalline lens, or by drawing the lens  towards the pos-
terior part  of the  eye,  by means of a  few muscular fibers
called the ciliary muscle, running from the bones of the nose
to the  cornea,  which by  their contraction would force the
aqueous humor upon the crystalline lens in such a manner as
to flatten it, and by a relaxation of the same fibers a dilata-
tion in  an antero-posterior direction  is effected, and that in-
stantly.
   701  Experiment for Seeing  the Arteries of  one's own
Eye.—The  image  of the arteries of one's  own  eye  can be
readily seen in the following manner.  In a dark  room place
the left hand over  the left eye,  and in the right hand  hold a
lighted candle  by  the right side  of  the  head,  and very near
to it.    Then  with  the right eye open, looking towards the
darkened Avail,  move the candle up and down  rather quickly,
and in  a few seconds dark branches will appear at a short dis-
tance from the eye, looking like the  limbs of a tree, which are
images of the arteries distributed on  the  retina.

   702. Limits of  Vision.—What is the size of minute ob-
jects  that can  be  seen  by the naked eye ?  Ehrenberg, an
eminent microscopist, says that  nearly all eyes  have equal
power to discern minute objects, whether long or short-sighted.
The  smallest  square magnitude  visnVe to  the  naked  eye,
either of white particles on a dark  ground, or the reverse,  is
about the TL^th of an inch.   Brilliant  particles  which pow-
 ITow is the telescopic and the microscopic power of the eye explained ?  701. How can
we see the image ol the arteries of our own eyes?  702. What is the smallest square sur-
face that ean be seen with the naked eye ? 
AND  PHYSIOLOGY.
383
erfully reflect light may be distinctly seen when  not half the
size of the foregoing.   Thus gold dust the TT_sth part  of an
inch in diameter is visible in common daylight.    Lines may
be more i eadily seen than points.   Opaque threads T¥V „ th of
an inch in diameter can be seen when held  towards the  light.
Attention  also  greatly helps to discern  minute  objects, or at
least to retain them in sight when once pointed out.  Thus
we are often able to see a faint star in the sky or a ship  in tha
horizon after  they have been pointed  out to us, although they
were not  seen  before.  " I myself," says Ehrenberg, " can
not  see  .V?.th of an inch, black or white, at twelve  inches
distance ;  but  having found it at from  four to five  inches
distance, I can remove it to twelve  inches and  still see the
object plainly."
   703.  Color Blindness.-Many people are afflicted with an
 inability to distinguish certain colors of the solar spectrum.
 This is called Color Blindness, or Daltonism.
   704.  Formerly it was supposed that this affection was very
 rare, but  later researches show it to be quite common.   Ac-
 cording to experiments made by Dr. Wilson  upon 1154  per-
 sons in Edinburgh in  1852 and 1853, it was found that—
                  1 in 5 j confounds red with brown.
                  1 iu 60 confounds brown with green.
                  1 in 43 'confounds blue with  green.
   Hence one in every 17.9 persons  is color blind.


     THE   SENSE   OF  VISION IN  ANIMALS.

    705. Tapctum —Pupil —Nictitating Membrane—Harde-
 rian  Gland.—The general anatomy of the eye of mammab
 differs but slightly from that of man.  Between the sclerotic
 and choroid in some animals is found another membrane of a
   How is it with brilliant particles?  How is the ready vision of lines compared with
 points?  How small  a thread can be seen by the naked eye? What effect has the fa-
 miliarity with an object ? 703. What is color blindness ? How often is this peculiarity
 found ?  What colors are most commonly confounded ?
                            17 
384           HITCHCOCK'S   ANATOMY

metallic  brilliancy,  with  different shade of color, known as
the Tapetum.  In horses  and coAts it has a variegated luster
of green  and blue, while in the tiger, cat, and  whale it is of
a  silvery brightness.   The shape of the pupil in the  wolf
and dog,  which need vision in all  directions, is  circular ; while
the fox and  cat, which need a vertical  range more than  any
other,  have a perpendicular slit only.   In cattle and the more
timid grazing animals which obtain their food from the ground,
and need to look behind with ease Avhen pursued, the pupil is
a  horizontal ellipse.   Nearly all mammals except man  and
the apes, have a  third lid, which is a transparent membrane
that is frequently slid over the  ball by a peculiar muscular
apparatus.   This is called the " haw" or  Nictitating Mem-
brane, and, especially in birds, serves the purpose of remov-
ing impurities from the eye, and also of spreading  the secre-
tions over it, in  order to keep it  moist and  transparent.   In
addition  to  the  lachrymal gland, in all  animals which  haATe
the third lid there is another gland called the Harderian Gland,
which prepares another secretion  similar to and for nearly the
same purpose as the lachrymal.
   706.  Eyes of Birds—Pecten  Marsupium— All birds,
without  exception, are provided  with perfect  and Avell devel-
oped eyes.   They are  always large, and  largest in  birds of
prey.   They are but slightly  movable themselves,  but  this
want of  motion  is compensated  by the great  mobility of the
head.   The sclerotic coat  is strengthened  in front by a series
of bony  plates, fourteen or fifteen in number, interposed be-
tween its  fibrous layers,  a great use of which is to give at-
tachment to the special muscular apparatus for adapting the
e /e to see objects at different distances.   The anterior chamber
 i proportionally larger than in any other animals, so that the
iris is far back from the cornea.   The iris has  different shades
of color, commonly yellow or brownish.  The yelloAv color of

  705. What is the tapetum ? What is its color? What is the shape of the pupil in the
wolf, dog, and in cattle? What is the Nictitating membrane?  Of what service is the
" haw ?" For what purpose is the Harderian gland ?  706. What is said oi the perfection
of eyes in birds? How is the sclerotic coat strengthened in them ?
'\ 
AND  PHYSIOLOGY.
3&5
this part in the owl is owing to the presence of cells  contain-
ing fat.  A curious structure is found in the eye of birds that
is found in no other  animal.   It is called the " Pecten Mar-
supium," and consists of a layer of blood-vessels arranged in
several plications varying greatly in size.   It extends some-
times as far forwards as the lens, and is covered  by black pig-
ment.   Its probable use is that of absorbing  rays that enter
tie eye obliquely, and  thus rendering sight from a forward
direction more definite and  sharp.   The  membrana  nictitans
and the Harderian glands are present in these  animals in their
fullest perfection.

   707. Eyes of Reptiles.—All reptiles have t ,vo eyes.   In
most,  especially in serpents, they aro small in comparison
with the size of the body ; in the frog, hoAvever, in the  gechos
and chameleons they are large.   In some they are covered  by
the skin.   In the serpents  there are no eyelids, but the skin
which  covers  them is kept  moist by a lachrymal gland, and
thus performs the  service of a lid.   In  other reptiles there
are three lids, the middle one of  which moves at right angles
to the  other two.   The  lachrymal gland  often is very large.
In  some  turtles and  lizards there is a  ring of bony plates
which  supports the eyeball.  The lens has  different degrees
of sphericity in  different animals.

   708. Eye  of Fishes—Pigmentary  Spots.—The  eyes  of
fishes are remarkable  for the great size and spherical form of
the lens, which  is necessary in order  to give  sufficient  refrac-
tion to the rays  of  light that come from the  dense medium in
which  they live.   The  size of  the lens varies greatly, being
largest in the bony  fishes  and  smallest  in  those  which  lie
brried in the mud  like  the eel.   The lowest stage,  however,
is seen in the amphioxus,  a condition which greatly resembles
 What makes the yellow color of the iris in birds?  What is the pecten marsupium?
What is its use? 707. What is said of the eyes of reptiles?  What of the bony plates
in the eyeball ?  708. What characterizes the eyes of fishes ?  What ones have the
largest ? 
38»j
HIT 0 II C O 0 K ' S  A N A T <> M V
Fig. 354.
that of the  lowest  invertebrata, being nothing  but  two pig-
mentary spots.   The eye is  but  slightly  movable in fishes,
since the body, and consequently the head, can  be so readily
moved in any direction through  the  water.
                                       709.  Compound   Eyes
                                    — Number  of Facets.—
                                    The eyes  of many of tha
                                    articulate animals are con-
                                    structed  upon the   com-
                                    pound  type,  that  is, the
                                    visual organs are made up
                                    of an aggregation of single
                                    eyes placed upon  each side
                                    of the  head, each one  of
                                    which is a complete visual
                                    instrument,  but  can re-
                                    ceive and  bring to a  focus
                                    only  those rays  of  light
which come to it from  a particular direction.  In many  in-
sects each  composite  eye  forms a  hemispherical protuber-
ance upon the side  of the head,  Avhich, when examined by the
                            Fig. 355.
  Head and Compound Eyes of the Bee, show-
ing the Ocelli in situ  on one side (A), and dis-
placed on the other (B).  a, a, a, Stemmata. b,
b, Antennte.
 A, Section of the Eye of Melolontha Vulgaris (Cockchaffer). B, A portion more highly
Magnified,  a, Facets of the Cornea, b, Transparent Pyramids surrounded with Pig-
ment, c, Fibers of the Optic Nerve, d, Trunk of the Optic Nerve.

 What are the pigmentary spots?  709. What are compound eyes? What sub-kingdom
do they characterize? How does the eye appear on many insects? 
AND  PHYSIOLOGY.
387
magnifying glass, is found to be made up of a vast  number
of facets,  which are  generally  hexagonal.   In the common
house  fly  there  are 4,000  in  each eye, in the  dragon fly
24,000, and in one  species of the beetle  25,000.   Each  one
of these facets is found to be the end of a little  eye, the frus-
trum of a slender pyramid standing by its apex on a bulbous
expansion of the optic nerve.   The interior of this pyramid
h  filled Avith  a trans-               Fig. 356.
parent substance which
represents the  vitreous
humor,  while  between
the frustra is found the
black  pigment.   Both
Surfaces  Of these facets   Eye of possji Tribolite constructed ou tho  same
are found to be  convex,  Plan-
and  it  has  been  calculated that the focus of these lenses would
be at a point just  at  the extremity of the pyramid where it
joins the optic nerve.   And  since the rays of  light entering
one of these facets can not enter the other on account of the
black pigment intervening between  them, the range of vision
to the  insect would necessarily be very limited  were it not for
their enormous multiplication, by which in reality a separate
eye is  provided for every point  to  be viewed, thus giving to
the insect  as perfect  an apparatus of vision as Ave have, al-
though immovably fixed  on  the body.
  710. S t e m m a t a .—Besides the composite eyes, insects usu-
ally  have a small number of simple eyes situated upon the top
of the head, called Stemmata.   If they are covered  with paint,
the movements of the  insect are constantly upward.
  711. Other  Articulates.—A few insects that live  in dark
places  have no eyes.   Some Crustaceans have compound eyes
without facets, and others with them.   Some Annelids have
eyes, others none.   The  Rotatoria have vision,  but the Hel-
 AVhat number of facets arc there iu the house fly and in the dragon fly? Give the an-
atomy of each facet or pyramid. 710. What other organs of vision besides compound
eyes do insects have?  If the stemmata are removed what is the result?  Til. What
of the eyes of articulates ? 
388            HITCHCOCK'S  ANATOMY

minths  are  without eyes.   Among Arachnida  (spiders)  the
eyes bear a near relation to the vertebrate type of eyes.  Their
number is much less than among the other articulata, seldom
more than eight, and are to be compared more with stemmata
than  with  compound eyes.   Sometimes these are  collected
into  one mass upon the second segment of the body, and some-
times they are arranged symmetrically upon the median lino.
   712.  Eyes of  Molluscs.—The organs of  vision in  the
Acephala are numerous,  rising as high as forty in the genus
Pinna, Avhere they are placed  in the mantle.   The Cephalo-
phora have generally two eyes.   In the Cephalopoda the eyes
are disproportionately large, and  possess nearly all the parts
found in the eyes of vertebrates.
   713.  Eyes of  Radiates.—The  Polypi  show a  sensibility
to light, but no  eyes  have been discovered  in them.  The
Acalephae seem to have the sense of vision, and Agassiz seema
to have  ascertained the presence of an organ for this purpose
in some of them.   It is more doubtful in respect to the Echi-
noderms.
 AVhat eyes have spiders?  712. What are the eyes of molluscs?  713. What is said of
the organs of vision among radiates ? 
AND   PHYSIOLOGY.
389
              THE   SENSE  OF  HEARING.

          DEFINITIONS  AND   DESCRIPTIONS.

   714.  Parts  of the Ear.—The organ of hearing is made
up of three distinct portions:  the  Pinna or external ear, the
Tympanum or middle ear, and the Labyrinth or internal ear.

   715.  The  Pinna.—The  Pinna, commonly known  as the
Ear,  is a cartilaginous plate  with numerous irregularities upon
its surface, and having  upon  it a few muscular  fibers, which

            Fig. 357.                          Fig. 358.
  _ View of the Left Ear in its Natural
_ \U\  1, 2, The  origin and termination
or th« Helix.  3, The Anti-Helix.  4, The
Anti-Tragus.  5, The Tragus.  6, The Lo-
bus of the External Ear.  7, Points to the
Scapha, and is on the front and top of the
Pinna.  8,  The Concha.  9, The Meatus
A'"Mtorius Externus.
ral      An Anterior View of the External Ea _
ion    as well as of the Meatus Auditorius, Laby-
'he    rinth, etc. 1,  The Opening into the Ear
_o-    at the bottom of the Concha. 2, The Mea-
the    tus  Auditorius Externus or  Cartilagin-
the    ous Canal.  3, The Membrana Tympani
tus    stretched upon its Eing.  4, The Malleus.
      5, The Stapes.  6, The Labyrinth.
714. Wbat are the three parts of the organ of hearing?  715. Describe the pinna. 
390
HITCHCOCK'S  ANATOMY
are in fact rudimentary muscles,  5 in number.   In some men
they  have been  so fully  developed that the  ears  could  be
moved by their action,  while among quadrupeds there are but
few  that  do not possess  this power.   The Pinna somewhat
resembles a funnel, forming at its base an irregular tube called
the Auditory Canal, about half an inch in diameter and  an
inch  in length, which  terminates  with the Tympanum.   A
i ;w stiff hairs are found upon the sides of this  canal, and  in
the lining membrane some glands, which secrete the Avax  of
the ear.

   716.   The Tympanum.—Membrana  Tympani  — Little
Bones  of  the Ear.—The Tympanum  is an irregular  cav-
ity located in the petrous  portion of the Temporal  bone,
measuring rather  more than  one half inch  in its longest
diameter.   At the point  where  the   Auditory Canal  joins
                                     the   Tympanum,   the
              FlG- 359-                 Membrana Tympani is
              ff            &         found, which is simply
                                     an  impervious  mem-
                                     brane stretched between
                                     the  two   cavities,   dip-
                                     ping inwards at an an-
                                     gle of forty-five degrees.
                                     To  this  membrane are
                                     attached  three muscles
                                     for the purpose of ren-
                                     dering this  membrane
                                      lax or tense, as may be

  View of the Cavity of the Tympanum, the Ossicnla Auditus, and their Muscles, magni-
 fied,  a, a, Cavity of the  Tympanum,  b, Membrana  Tympani, or rather the osseous
 circle to which it is attached, c, Handle of the Malleus, resting on tho middle of the
 Membrana Tympani. d,  Head of the Malleus articulating with the Incus,  e, Long
 Handle of the Malleus, passing into the Glenoidal Fissure ; the Anterior Muscle of the
 Malleus is attached to it.  f, Internal Muscle of the Malleus, g, Anvil,  h, Lenticular
 Bone,  i, Stapes,  k, Muscular Stapedius.
 Can the ear ever be moved ?  How many rudimentary muscles are placed on it ?  71&
What is the tympanum ?  Describe the membrana tympani. 
AND  PHYSIOLOGY.
39i
     Fig. 360.

A                D
Fig. 361.
  a   b
A
 Membrana Tympani from the Outer (A), and from
tie Inner (B) Sides. 1, Membrana Tympani. 2, Mal-
leus. 3, Stapes.  4, Incus.
             d
 Small Bones of the Ear. a, Tha
Malleus,  b, The Incus, c, The
Lenticular Bone, d, The Stapes.
required.  This cavity contains the " little bones of hearing,'1
as they are sometimes called.   These are the Malleus, a ham-
mer,—the Incus,  an  anvil,—and  the  Stapes,  a stirrup, be-
cause they someAvhat resemble these instruments.   The Mal-
leus lies  directly against the drum of the ear (Membrana
Tympani), its opposite side connecting with the Incus,  which
is in connection with the end of the Stapes, thus  forming a
continuous chain of  bones through the  Tympanic Cavity.  In
the walls of the Tympanum are no less than  ten  openings,
the most important of  which are, one  downwards into the
Pharynx  known as  the  Eustachian Tube, another into the
Labyrinth, Avhich is closed by the foot of the Stapes, and an-
other outwards to the External Ear.
   717.   Labyrinth.—Cochlea.—Semicircular  Canals —
Perilymph.—V e s t i b u 1 e.:—The Internal Ear is called a Laby-
rinth because of  its  very  complicated  structure  and  func-
tions.   (Fig. 362, p. 392.)   It mainly consists of  a series of
semicircular  canals and  cavities,  of which  some are made up
of cartilage,  and others of bone.   The  canals are composed of
bone, three in number, and their respective planes arrang^d at
riodit angles  to each other.   They contain the  nerves of near-
ins: and other substances, which facilitate the transmission of
sound.   One of these portions is named the Cochlea, because
 What are the names of the bone6 of the ear ?  How many openings are there tri tha
tympanum? T17. What is the labyrinth? Of what is it mainly made up? 
392
HITCHCOCK'S  ANATOMY
FIG. 362.
  i Vie* of the Labyrinth and Tympanum of the Ear, with the Bones in Situ, highly
mafliflt-d.  1, Processus Longus of the Malleus. 2, Its Processus Brevis.  3, Its Manu-
brium.  4, Its Neck.  5, Its Head.  6, Body of the Incus.  7, Its Processus Brevis.  8,8,
Its Processus Longus, with the little head for articulating with the Stapes.  9, The Head
of the Stapes.  10,  Its Anterior Crus.  11, Its Posterior Crus.  12, Its Base.  13,14,15,
The first turn of the Cochlea.  16, 17, 18, Its second turn.  19, Its  half turn.  20,  The
Cupola.  21, The Fenestra Rotunda.  22, 23, The Vestibule.  24, 25, 26, Anterior Semi-
circular  Ctiul.  27, Its junction with the Posterior Canal.  28, 29, 30, 31, The Posterior
Bemicircilar Canal.  32, 33, 34, 35, The External Semicircular Canal.  The Enlargements
on these Canals are called Ampulla".

it resembles a snail shell, and some of the others semicircular

canals, because  they  are  tubes  containing fluid  called  Peri-

                                  FiG. 363.
Cochlea without the Nerv«. 
AND  PHYSIOLOGY.
393
lymph and nerve fiber, which take the general direction  of a
semicircle.   Of these cavities,  however,  the cochlea  is  not
filled with the perilymph, but contains the finest subdivisions
of the auditory nerve.   Besides the cochlea and semicircular
canals there is a small three-cornered cavity called the  Vesti-
bule, into which the five openings  of the  semicircular  canals
enter.

   718. Auditory Nerve.—The nerve  of hearing belongs to
the  eighth  pair  of  Cranial  nerves.    It  divides  into  two
branches just before it enters the ear,  one of Avhich  is called
the cochlear branch, because it is sent  to the cochlea, and an-

                           Fu. o64.
  Auditory Nerve taken out of the Cochlea. 1, 1, 1, Trunk of the Nerve. 2, 2, Its fila-
ments in the Zona Ossea of the Lamina Spiralis.  3, 3, Its Anastomoses in the Zona A'esi-
•ularis.

other the vestibular, since it enters the vestibule, a portion  of
the labyrinth.   Besides this a branch  of the  facial nerve en
ters the ear  in company with the auditory.

   719.  Location  of  the  Internal  Ear.—In man and all
the higher animals there  are  two  separate  organs  of  hearing,

  Describe the cochlea.  What are the semicircular canals ?  What are they filled with ?
71S. What is the nerve of hearing ?  710. In what bono is the ear located ? 
394           HITCHCOCK'S  ANATOMY
_r an ear upon each side of the body,  and no internal connec
tion exists  between them, so that  one may be injured  or  de-
stroyed while the other performs its office.   In fact, the inter-
nal ear is protected by the hardest bone (the temporal) in the
body, and is  inclosed in a bony sac to Avhich the only opening
of any considerable size is that of the auditory canal.
             FUNCTIONS  OF  THE   EAR.

    720.  Functions of  the Pinna.—The object of the pinna is
 to convey sound to the auditory canal.  This  it  does by con-
 duction and convection ;  that is,  it acts as a funnel to  collect
 the vibrations of air and transmit them to the auditory canal,
 and also conducts sounds by means of its OAvn  substance in
 the same manner as a  stick of timber conveys the sound made
 by the scratching of a pin to its opposite extremity with great
 distinctness.   Hence the use of the external ear is to  collect
 sounds from as large a surface as possible, and concentrate
 them at the small end of a funnel, so as to increase somewhat
 their intensity.  The probable  design of the  ridges and  fur-
 rows upon the pinna is to give a greater exposed surface to it
 as well as to receive vibrations more accurately which come
 in various directions.
   721. Use of the  Auditory Canal.—The use of the audi-
 tory canal is to give greater intensity to the  sounds collected
 by the  external ear.   This can be illustrated by placing a
 long tube close to the ear, while another person speaks attiie
 other extremity.   The  voice will  be greatly increased  in in-
 tensity, because every vibration is transmitted  to the ear, and
 none are dissipated upon  the air  or surrounding  substances.
 The auditory canal performs the same office, although in a less
degree than in  the above experiment.   This canal dso  exists

ninn!ieTn7r>m'?UniCati°nbetWeenthe tW° eilrS? 72°- ™»t fs tb7i*jeJd7_,,
pinna?  How does ,t convey sound to the internal ear? Why is the plrna of «uch an
unevensurface? 721. Of what service is the auditory canal ? How may [uuse b^lus 
AND  P II V S I O L O G Y.
395
for protection to the membrana tympani and the delicate or-
gans of the ear, which  must  be placed within  the  head to
such a distance that no harm could come to them from exter-
nal violence.

  722. Function of Membrana Tympani—Use of the  "Lit-
tle  Bones."—The membrana tympani is a very thin and elas-
tic membrane, not half an inch in diameter, which is designed
to receive all  the  vibrations of the air falling upon  it.   On
this account it  is stretched directly across the auditory canal,
and is so arranged that  by means of  muscles  it  may be ren-
dered more or less tense, so that  if it is desired  to catch a
very faint sound, the drum may be made so sensitive  as to
catch the  slightest vibration.   The sound  received by  the
drum of the ear is transmitted to the  auditory nerve by means
of the chain of bones already mentioned, the broad side of the
malleus resting directly against the drum, and the  broad end
of the stapes closing the  opening in the semicircular canals
Avhich contain the nerve of hearing.   The use of this arrange-
ment seems to be to catch all the  vibrations of the  drum, and
instead of allowing  them to expend themselves upon the air
in the tympanum, to transmit them directly to the auditory
nerve.   The use of the cavity of the tympanum seems to be
to allow a free  vibration of the membrane of the  drum.   An-
other reason for the large size of the  tympanum  is to prevent
the conveyance of sound to any other part of the ear but the
semicircular canals, and that by means of the chain  of little
bones.   And in order to convey the sound  only  to the  nerve
of hearing the stapes joins on to the  canal, not by a solid ar-
ticulation, but simply by cartilage, so that none of the  vibra-
tions can be conveyed to  the walls of the canals, but  all to
the nerve.
  723.  Function  of Eustachian Tube—The design of the
 What does this canal protect? 722. What is the function of the membrana tympani ?
Of what use are the " little bones ?"  What service is rendered by the tympanum ? How
does the stapes unite with the canal ? 
;?96
HITCHCOCK'S  ANATOMY
Eustachian  tube is  evidently to allow of equal  atmospheric
pressure upon both sides of the membrana  tympani.   For
were the air in the tympanum closely confined, the  atmosphere,
varying as it does in density, would sometimes create such a
pressure on  the drum that all vibrations would be indistinctly
conveyed to the  brain.  This is the same arrangement that is
found in bass and tenor drums used for  musical  instruments,
a small orifice always being necessary to give free access to
the air.   Hence, when  we have a cold, or especially a sore
throat, where the mucous  membrane is inflamed, we often find
hearing difficult, because  the  lining  membrane  of the Eus-
tachian tube is so much swollen that air can not pass through.
Also when the same condition prevails Ave can, by swallowing
the small  amount of saliva in  the mouth  with  considerable
force, drive  so much air into  the tympanum that a sense  of
fullness occurs in the ear, which continues  until  the air  has
found some  means of escape.

   724. Functions of the  Internal Ear.—The uses of all the
parts belonging to the internal  ear are not perfectly under-
stood.   Probably, however, the labyrinth and cochlea serve
to give as great expansion as  possible  to  the nerve in  the
small space  provided for it.  And the use of  the  fluid filling
the labyrinth is  to secure  all the vibrations coming in through
the bones  of hearing, and  give them greater intensity.   Some
experiments worked out  by Muller,  a German  physiologist,
throw  considerable  light   on  the  subject.    He  found  that
sounds passing directly into water  from the air lose consider-
able of their intensity ;  but if a tense membrane is placed be-
tween  the two, greater  intensity is produced.  The  intensity
is also greatly increased Avhen to this membrane is attached
si small solid body Avhich communicates Avith the water alone.
This seems to show Avhy the drum  receives all the sound
 723. What is the use of the Eustachian tube ?  In what instruments of music is there
,isimilar arrangement?  Why does partial deafness sometimes accompany a cold ? 724.
What is said of the functions of the internal ear ?  Relate the experiments made by
Muller. 
*
                 AND  PHYSIOLOGY.              397

rataer than some other part of the ear, and also the value of
the three small bones of the ear, at one extremity fastened to
the drum and at the  other  by cartilages to the  semicircular
canals.   Other experiments  also  showed that a solid body of
the form of the stapes  alone was the best to communicate with
the auditory nerve.
   725  Function of the Cochlea and  Semicircular Canals.
—It has been thought by some that the  cochlea enables one
to determine the pitch of sound, since  animals which possess
the fullest development of this  organ have the largest  range
of voice.  Another speculation is, that the semicircular canals
aid in the  determination of the direction from which sounds
come,  since  in  animals  where  they exist, they are always
placed at right angles to each other.
   725 a. Three Physical Properties  of Soun:!.—The  three
physical peculiarities of sound are intensity or loudness, pitch
or length of the waves, and quality, or the difference between
the same note on a flute and violin, although equal in intensity
and pitch.   And a theory has been proposed, substantiated by
many facts, that the membrana tympani enables us to deter-
mine the intensity, the cochlea the pitch, and the  semicircular
canals the  quality of sound.
           THE  SENSE OF  HEARING  IN ANIMALS.

  726.  External Ears—Semicircular  Canals—Cochlea—
0 s  Quadratum.—All mammals; as  a general rule, have ex-
ternal ears.   These, in some  animals, like the  bat, are enor-
mously developed in proportion to the dimensions of the bod;.
Besides, in several genera they can be turned in  any direction
the  animal may choose.  In man the ear consists of but  one

 725. What suggestion has been made of the use of the cochlea and semicircular canals?
725 a. What are the three physical peculiarities of sound ? 726. What mammals have
external ears?  What is said of them in the bat? How many pieces has the pinna in
most animals? 
398
HITCHCOCK'S  ANATOMY
 piece, while in the other mammalia it consists of three.   But
 the most important  part of this organ, the labyrinth,  agrees
 in its  structure  throughout  the whole class.   The greatest
 variation that exists is in the semicircular canals and cochlea.
 In the cat the canals form the  segment of a  circle, Avhile  in
 the goat they furnish a portion  of an ellipse,  and in the horse
 a parabolic curve.   The  cochlea varies in the number of its
 coils.   In the whale and dolphin it makes but one and  a half
 turns ; in man two and a half;  in the  ornithorynchus  half a
 coil much resembling that of  a  bird ;  Avhile in the squirrel  it
 makes  nearly  four  turns.   No physiological effect of these
 variations has as yet been given.  In  man  and  the apes the
 Avhole cavity of the  tympanum is concealed  in a portion of
 the temporal  bone, but in all  other mammals  we  find a pecu-
 liar tympanic bone which varies exceedingly  in the different
 classes.
   727.  Ear  of Birds.—There are but few birds Avhich have
 any thing like an external ear.  One species of owl,  however,
 has  a  membranous concentric fold  which can be used as  a
 valve.    The cochlea  has the form of an obtuse cone, which at
 its extremity swells  into  an  oval  tubercle.   The  tympanic
 cavity communicates with cavities in the cranial bones,  which
 greatly increases the resonance of sound, in the same manner
 as the  sounding-board  in the piano, or the main body of  a
 violin or violincello.
   728.  Hearing  in  Reptiles.—Although  reptiles present a
 more imperfect  form of the  organ of hearing  than mammals
 or birds  yet  they possess  the tympanum, a membrana tym-
 pani, and a chain of  ossicles  or little bones.   Also a cochlea
 is found, which is most fully developed in crocodiles and formed
almost as in birds.
 How do the canals differ in different animals? What variation in the cochlea?  What
.s the os quadratum? 727.  What bird has external ears?  What is said of the cochlea
in birds? What does the tympanum communicate with?  What is the use of this ar
^angement ? 728.  What fr  ,aid of the organs of hearing in reptiles ? 
AND PHYSIOLOGY.
399
  729.  Hearing  of Fishes.—Among the lowest  order  of
fishes the organ of hearing is  simply a sac, which is full of a
fluid that contains small bones or bits of bones called otoliths,
and  the auditory nerve is  distributed upon its walls.   In
almost all fishes there is a more or less perfect form of the
semi-circular canals.  In  some  fishes  the  SAvimming bladder
extends to membranous spaces  in the  cranium which  are in
connection Avith an auditory apparatus.
  730.  Articulates.—Among  the Crustaceans hearing has
been  observed  only among the Decapods.   The sense  exists
in the Arachnoids, but no organ has  been found.  The same
is true of Insects,  Annelids,  and Helminths.
  731.  Molluscs.—Hearing has been ascertained in Lamelli-
branchiata.   In Cephalophora  it is  of a low grade: but an
auditory nerve and organs exist in the Cephalopoda.
  732.  Radiates.—The organ of hearing exists in the Polypi
and  perhaps the  Acalephs,  but  has  not been  discovered in
the other Radiates.
                 SENSE  OF  TOUCH.

       DEFINITIONS  AND  DESCRIPTIONS.

  733.  Location of the  Sense of Touch.—The organ of touch,
with the exception  of the upper surface of the  tongue, is the
skin.   This in some parts is much  more  sensitive  than in
 729. Do fishes have the regular organs of hearing? What organs do they have in a
rudimentary state ? 730. What apparatus of hearing do articulates possess ?  Do they
seem to hear sounds?  731-732. What is said of the sense of sound in molluscs and rar_
ates?  733. Where are the organs of touch located? 
400
HITCHCOCK'S   ANATOMY
others, since some portions of the skin are more fully crowded
with nerve fibers than others.   We are conscious of resistance
if  we place a substance in contact Avith any part of the body;
and  although Ave are able with the tips of the fingers to tell,
Avhether a body, which is pressed on them, is circular or rect-
angular,  yet we can not with certainty decide the same thing.
if the substance be pressed upon any other part of the body.
   734.  The Direct Instruments of  Touch.—The direct ii«
struments of sensation are minute loops of nerve  fibers from
the posterior roots of the Spinal  Column, lying in  the  true

                         Fig. 365.
Nerves of Sensation at the Extremity of the Human Thumb.
skin, Avhich are  covered only by the Epidermis, as is seen in
Fio*. 365.  These nerA'es of sensation are never known to ter-
minate in a free  extremity, but always  in loops;  and in  the
hand  and foot are associated with  the  Pacinian  Corpuscles,
described under the nervous system.
          Fig. 366.                 735.   P a p i 1 1 EC---Those
                                parts of the  skin which  are
                                the  most  sensitive,  are  cov-
                                ered with  minute  projectioi l
                                called Papillae,  which  seem
     ^^i-^^^-'^S':^'       to be mere elevations beyond
   Papiite of the Palm of the Hand.     the  general  surface of  the
  What is said of the whole cutaneous surface ?  734. What are the immediate instru-
 ments of touch?  How do the sensitive nerves always terminate ir  735. Describe tha
 papilla!.
 
AND  PHYSIOLOGY.
401
skin, in which are found the loop of a  nerve, and a  blood'
vessel with some cellular tissue.  The main use of them seems
to be to place the nerve in such a position, that it will be most
easily impressed with whatever external substances it may be
brought into contact.


                      FUNCTIONS.

   736.   The   Superficial   Parts   of  the   Body   most
abundantly   Supplied  with  Nerves.—The  parts  of the
body lying  deep beneath the skin, are but sparingly supplied
with nerves of sensation, which is a great comfort  to those un-
fortunate  persons Avho  are  subjected to surgical operations,
since the  most  painful  part  is in cutting through the skin,
which is the quickest part of the operation.   This, however,
is the case only Avhen the deep parts  are  in health (including
the bones) ;  for if any of these parts, and especially the bones
and  ligaments,  are  diseased, they constitute  a source of the
greatest pain.   The necessity of this arrangement is obvious
from the  protection  which  the surface  of  the body requires
from violence and heat.   Were it not for these body-guards,
we by our other senses should  seldom know when friction or
heat  was consuming the skin,  nor when  cold  was destroying
its vitality.
   737.  Value of this  Sense to  the  Blind.—To those de-
prived of the sense of vision, this sense is of great value, since
it is by this only that they  are enabled  to pursue any  labor,
or  instruct  and  please themsekes  by  raised alphabets, or
play upon musical instruments.   And it is interesting,  not to
say wonderful, to see  what accuracy  is acquired by the blind
in detecting true from spurious coins, or in distinguishing the
quality of cloth  by  feeling alone.  It is said on good  author-

  What is the function of the papilla;? 736. Why are the superficia. parts of the body
the most abundantly supplied with sensitive nerves ? Why does the skin need  sensibil-
ity ? 737. What is said of the value of this sense  to the blind ? What example* ve
mentioned as illustrating its extreme acutencss in the blind? 
.02
HITCHCOCK'S  ANATOMY
ity,  that  one blind man became a  botanist,  another a con-
chologist, and another a land surveyor, simply by the aid of
touch.
   738.  Effect  of  Habit  on   Location  of  Sensation —
Habit has a Avonderful power in the  location of sensations on
the skin.  Thus it is frequently the case, after an amputation of
a limb, that the patient declares that he feels  pain in the re
moved portion.  This is owing to some irritation in a fiber or
fibers  of the  remaining nerve  trunk, which  were originally
sent to the supposed seat of the pain, and from habit  the suf-
ferer locates it in the removed  part.  Also after the Talia-
cotian operation—which consists in  making a new nose  from
the  skin  of  the forehead,—if  the   nose  itches, the  patient
scratches the forehead as the seat of the irritation.
   739.  Insensibility  produced   by  a   long  continued
Action of  some  painful  Stimulus.—It is sometimes the
case that the nerves are rendered insensible by  the moderate
but long continued action of some painful stimulus.   A  com-
plete insensibility  of the skin  may  be produced, so that the
severest surgical operations  may be  performed Avithout pain,
by the application of snow and  salt  mixed in equal portions.
Heat will also do the same thing, as  shoAvn  by the folloAving
example.   "A traveling man one Avinter's evening laid  him-
self  down upon  the platform of a lime kiln, placing his feet,
probably benumbed by  the cold, upon  the  heap of stones
newly put on to burn through the  night.   Sleep overcame
him  in this situation : the fire gradually rising and increasing,
until it ignited the  stones upon Avhich his feet  were placed.
Lulled by the warmth the man  slept on; the fire increased
until it burned one foot and  part of the leg  above the ancle
entirely off, consuming  that  part so  effectually that a cinder-
like  fragment Avas alone remaining, and  still the wretch  slept
on, and in this state was found by the kiln man in the morn-

  738.  What effect has habit upon localizing our sensations? 739. How may insensibility
b« sometimes brought about ?  What wonderful example ? 
AND  PHYSIOLOGY.               403
ing.   Insensible to any pain, and ignorant of his misfortune.
he attempted to rise and resume his journey, but missing his
shoe, requested to  have it found :  and when he was raised,
putting his burnt limb to the ground  to support his body, the
extremity of his  leg bone—the tibia—crumbled into  frag-
ments, having been calcined  into lime  Still he expressed no
sense of pain, and probably experienced none, from the  grad-
ual operation of  the fire, and  his own torpidity during  the
hours his foot Avas consuming."
       THE  SENSE  OF  TOUCH  IN  ANIMALS.

   740.  " It is probable that among the lower animals  the
proportion of intuitive perceptions is much greater  than in
man ;  whilst on the other hand  his  power of  acquiring  per-
ceptions is much greater  than theirs."

   741.  Touch  in  Mammals.—Cat,  Rabbit,  Elephant,
B a t.—Among  Mammals touch ordinarily depends  on little
projections known as papillae, Avhich contain a  loop of a sensi-
tive nerve.   In man this structure is principally found in the
tips of the fingers, but in the Monkey it  is found in  both the
hands  and feet.   In a majority of mammals  the  surface of
the nose, upper lip, and the vibrissse or  whiskers,  as  seen
on the  face of the cat,  are  organs adapted to  the  sense of
touch.    Cats are unable to  catch  mice when  these  whiskers
are removed, and Rabbits Avithout the assistance of their  eyes
can by means of these hairs find an outlet in a very narrow
passage.  In the Elephant this sense has  its  seat at the ex-
tremity of the  proboscis.   The wing of the Bat possesses an
extraordinary sensitive poAver.  It is  said that this animal i3
 740. AVhat is said of the intuitive perceptions of the lower animals ? 741. Where is
the sense of touch most perfectly developed in animals ? Of what use are the whisker!
of the cat and rabbit ? Where is the sense of touch in tha elephant ? 
404             HITCHCOCK'S  ANATOMY

able to fly through  perfectly dark  and irregular narrow pas-
sages, and avoid all obstructions simply by the delicate sensi-
bility of its membranous wings.

   742. Touch  in  Birds.—The only portions of the skin in
Birds, on which tactile  papillae  exist, are found on the under
surface of the foot, and the web of the web-footed birds.  The
bill of the Duck  seems also to  subserve the sense of touch,
upon the  inside  of which the  skin is soft, and has  many
branches of the fifth pair of nerves distributed to it.

   743. Touch  of  Reptiles.—The sense of touch seems to
exist in Reptiles,  though the  prominent use of the skin is to
afford a protection to the body.  It is quite probable  that the
acuteness of this sense in these  animals is  no greater than
what is derived  to the  Horse  through  the hoof, or to a man
through a stick or rod in the hand.

   744.  Touch  of  Fishes.—Fishes probably  have   a still
more imperfect  sense  of touch  than  Reptiles.   It  is pos-
sible  that  the  lips  may give an  imperfect idea of the form
of external objects; but  the  surface  of the body,  covered
as it is  with scales and  a thick  mucous secretion,  can  be
of no service in this  sense.   A  few fishes have hair-like
appendages about the  head, which  put them in a condition
to be acquainted with the presence of external objects, though
they are  not by any means organs of active touch.

   745. Touch  of  Articulates—This  sense  is well devel-
oped in all the Articulates, and shows itself especially in the
antennae, the palpi,  and feet;  and though these organs have
a tough,  hair-like consistence, yet they  are  efficient  instru-
 Where in the bat? 742. AVbere are papillae found in birds? AVhat answers the pur.
pose of papilla) in the duck ? 743. What is said of the sense of touch in reptiles ? 744.
Where is the sense of touch located in fishes ? 745. Describe the sense of touch in artico.
la tea. 
AND  PHYSIOLOGY.               405
ments  of  sensation.                 Fig. 367.
"For just as a blind
man judges  of the
proximity and char-
acter of  objects  by
the impressions  com-
municated to his hand
1/ the contact of  his
cane, with which  he
examines  them,  so
may an  insect  or
crustacean    receive              N~Ne>^^e
sensory  impressions
l\>  ^11
from the nerves  dis-                 A Foot of a Fly.
tributed to the basal joints of their long antennae, although
the organs themselves may be as insensible (or rather as un-
impressible) as the stick."

   746.  Touch of  Molluscs.—The sense  of touch in  this
group is well developed.   In some of the orders the organs
are from two  to  four contractile tentacles situated upon the
head, or the  anterior part of the back."   "With some Gas-
teropods these tentacles are holloAV and button-like at their
extremity, and can be im^erted like the finger of a glove."
   747.  Touch of  Radiates—"The  sense of touch is well
developed  among  the  Echinoderms."    It  exists  here  and
among other Radiates  in  tentacles or feelers.   Besides this,
other individual  Radiates  seem  to possess a sensitiveness of
the whole  surface of the body, though nerves can not be the
agents which secure this sense to them.
 Is it by an active touch that this sensation is gained by articulates ? 746. Describ*
touch in molluscs. 747. What is the touch of radiate* ? 
iOfl
HITCHCOCK'S  ANATOMY
SENSE   OF  TASTE.
DEFINITIONS   AND  DESCRIPTIONS.
   748. Anatomy of  the  Tongue.—The tongue  is  preJmi-
njntly the organ of taste.   Its principal part  is  made up of
           •Pig. 368.              muscular fibers Avhich run  in
                                 various   directions,  although
                                 they run in similar directions
                                 upon  the opposite halves of
                                 this organ.   The  tongue  is
                                 covered with a  thick mucous
                                 membrane,  Avhich contains  a
                                 large number of papillae simi-
                                 lar to those of the skin, which
                                 are of three kinds,  the Filiform,
                                 Fungiform, and Circumvallate.
                                 The  filiform are  from  one
                                 thirty-sixth to one eighth of
                                 an  inch  long,  of a conical
                                 shape, and are most abundant
                                 on the middle portion  of the
                                 tongue.  The fungiform  are
                                 situated upon the tip  and sides
                                 of the tongue,  and are some-
                                 Avhat smaller than the filiform.
                                 The  circumvallate  are from
                                 six  to twehre in  number, and
                                 are arranged  upon  the  base
                                  of the  tongue  in the form of
                                 the letter V, the apex pointing
                                  downwards.   They consist of
                                  a central  round  papilla flat-
 Front View of the Upper Surface of the
Tongue, as well as the Palatine Arch.  1,
1, Posterior Lateral Half Arches, with the
I'alato-Pharyngeal Muscles and Tonsils. 2,
Kpiglottic Cartilage, seen from before.  3,
3, Ligament and Mucous Membrane, ex-
tending from the root of the tongue to the
base of the Epiglottic Cartilage. 4, One
of the Pouches on the Side of the Posterior
Fraenum, in which food sometimes lodges.
5, Foramen Caecum. 6, Papillae Capitatae
seu Maxima;.  7, The  white point at the
end of the line, and all like it, are tho Pa-
pilla? Fungiformes.  8, Side of the Tongue
and Itugse Transversa; of Albinus.  9, Pa-
pilla; Filiformes. 10, Point of the Tongue.
 748. What is tho organ of taste ?  Of what is it made up, and with what is it covered f
Name the three kinds of papilla;.  Describe the filiform, fungiform, and circumvallate. 
AND  PHYSIOLOGY.
407
tened at the end, one twenty-fourth to one tAvelfth of an  inch
in diameter,  Avith a lower uniform  wall closely surrounding
the papilla.  More nerves are distributed to the circumvallate
than to either of the other forms of papillae.   At  its lower or
posterior  extremity the                FlG  369
tongue is attached to
the os hyoides, and at
its loAver  front  portion
to the lower jaw by the
fraenum   or bridle  of
the tongue ; so that it
is left free to move ei-
ther backwards or for-
wards by the  contrac-
tion of the appropriate  One of the  smallest Papilla; of the Tongue highly
muscles.                Magnifled-
   749. Blood-Vessels of this Organ.—A  great  quantity of
blood-vessels are distributed to this  organ, as can be seen by
looking at the under side of it, as well as by the free flow of
blood when it is wounded.
   750. Nerves  of Taste.—Of nerves there are no  less than
three large branches supplied to the  tongue from the  cranial
group : the  gustatory or  proper  nerve of taste, a branch of
the fifth pair which is  distributed  to the papillae ; the  glosso-
pharyngeal  distributed to the  mucous  membrane, being both
a nerve of motion and  sensation ;  and the hypoglossal distrib-
uted to the muscles, being preeminently a nerve of motion.


                      FUNCTIONS.

   751.  Use  of  the   Numerous   Muscular  Fibers  in   the
Tongue.—To effect the numerous  movements of the tongue in

  Which kind receive the most nerves?  To what is the tongue attached by its lower
extremity ? 749. What, proportion of blood is sent to this organ ? 750.  How many nerves
are sent to the tongue, and what are they ?
                            18
 
408
HITCHCOCK'S   ANATOMY
mastication,  swallowing, tasting, articulation, etc., it is neces-
sary that the muscular  fibers should run in various directions.
That, however, which  is  commonly known  as the  tongue is
only the tip  of it, while the largest portion lies in the front
and lower portion of the pharynx, where most of the  muscu-
lar actions are performed.
   752. Use  of the  Pa pi Use.—The  papillae  of the  tongue, as
those of the skin, are  constructed for  the purpose of giving
as much surface of nerve to be  exposed as possible,  leaving it
mostly in t e form of a loop.   The filiform  papillae are  not
the seat of the sense of taste or touch, but are analogous to
the lingual spines of lower animals (which gives such  rough-
ness to their tongues), which aid  in mastication  and  protec-
tion of the tongue.   As the sense of touch  is most acute at
the tip of the  tongue, it is supposed that the fungiform papillae
are the instruments of touch to the tongue ; and as we acquire
the sense of taste  more  at the  base  than at the tip  of  the
tongue, and as the nerves are more abundant and finest at the
circumvallate papillae, these probably administer mainly to the
sense of  taste.
   753.  Object  of this Sense.—The main use of  this sense i3
to direct  us  in the  choice of proper articles of food, and by
this means to  excite the flow of saliva  and  mucus, to aid  in
digesting food.  In man, however, this  sense would be an un-
safe guide, since this alone can not aid us to distinguish whole-
some from poisonous food, although many of the lower animals
seem able to make such a distinction by this sense alone.
   754.  Effect of Education on Taste.—Taste is made won-
derfully acwte by education.  Epicures are able to tell  the
manner in which game was killed, the spices used in cooking
it, and the length of time since  it Avas killed, Avhen  eating it.

 751. Why are there so many muscular fibers in the tongue ?  Where does the largei
portion of this organ lie ?  752. Of what use are the papillaa?  What sensation is gained
by  the filiform papilla??  In what papill® does the sense of taste mainly exist?  75a
What is the use of this sense?  Is it alone a safe guide for man?  754. Wha*  effect ha»
education upon taste ?  Give instances. 
                 AND  PHYSIOLOGY.              409

Wine tasters can readily give differences in the age, growth of
the grape,  and the  purity of wines, that to ordinary observers
are imperceptible.
   755. Taste  as Influenced by Smell.—Taste, as to some
substances, is dependent  on the sense of smell.   Thus, with
the eyes and nostrils closed, if an aromatic or spicy substance
be chewed it is impossible to say what the substance is, except
that it is pungent,  although it may be one with Avhich the per-
son is Avell acquainted.  Yet  smell  does  not aid us in deter-
mining the taste of acids, alkalies, or salts.
   756. After-Tastes.—An  important point connected with
this sense is that knoAvn  as after-tastes.   Thus, frequently
after eating sweet  substances a bitter taste is left  in the mouth,
and Avhen  bitter substances  have  been tasted a pleasant  ami
SAveet taste is left in  the mouth.   This subject is a matter of
great importance in the art of cookery.
            THE SENSE OF  TASTE  IN ANIMALS.

   757.  Use of  the Conical  Papilla;.—This sense is in all
animals confined to the tongue and inner surface of the mouth.
The sensation received from the sapid body is gained through
the papilla, which are present on the tongue and in  general
structure resemble those  of the skin.   There are probably
four kinds in mammals,  those  upon  the  central  part of the
tongue often being conical,  hard, and even  horny,  and those
upon  the back part fungiform, or soft  and  cup-shaped,  as is
seen in the tongue of the cat.   The conical papillae  seem to
act the part of a rasp, especially in  the  carnivorous animals,
in order to remove all the particles of meat from bones.   And
 755  Give the connection between taste and smell.  756. What is said of after-tastes?
757 How many kinds of papilla; in most mammals? What are the uses of the conical
papilla! to meat-eating animals ?  How powerful an instrument do these at times consti-
tute? 
IK)            HITCHCOCK'S  A X A T (> M A'

so efficient are these  that  the skin of  some of the more deli-
cate animals is removed simply by the licking of the tongue
of one of the more powerful carnivora.

   758. Tongue  of  Birds — In  the Woodpecker  and  Hum-
ming-Bird.—In  birds  this  sense is  very feeble,  since the
tongue is  destitute of sensitive papillae, and is often of a hard,
horny consistence, designed probably  more for  the  means of
obtaining  food than of judging of its quality.  In some birds
the tongue is  furnished Avith one or more ossicles for the  pur-
pose of giving stability and strength  to it.   In woodpeckers
the tongue is  not only long, slender, and  stout, but it is armed
                           Fig. 3*70.
Tongue.
                     Head of the Woodpecker.
with appendages like barbs on either side, in order that it may
be thrust into narroAv crevices in trees, to pierce and hold in-
sects upon which it lives.   (See Fig. 370.)   Humming-birds
have tongues very  slender and slit at  the  apex, so that both
sides can be formed into a sort  of tube by curving them to-
gether  from the  outside, in order that the bird may  suck
up  the  nectar  of floAvers.  And in  both  of these birds the
tongue  can be  extended for a  long distance in  front of the
body.

  759.  Tongue of Reptiles—Chameleon.— The  tongue of
most of the class of reptiles  seems to be constructed for other
purposes  than  that of  taste.   Like  that  of birds, it is pro-
vided with one or more lingual (tongue) bones, and is desti-
 753. How is it with the sense of taste in birds ? Describe the tongue of the woodpecker.
What is its use? What is the tongue of the humming-bird?  How far can the tongue
bo protruded in either of these animals ?  759. For what purpose is the tongue of rep-
tiles? 
                   AND  PHYSIOLOGY.               411

tute generally of papillae.   In some of this class  it is hardly
perceptible, while  in Serpents, Toads and the Chameleon, it
is very long and capable of rapid motion.  In Chameleons and
Serpents, when the tongue  is at rest, it lies in a kind of sheath
at the base  of the mouth.   That of the latter is forked  at its
apex, while the former  has a concave disk at its point covered
by a viscid  secretion, Avhich, by the dexterity of the  animal,
can be thrown at once  against the  insects flying in  tLe air,
thus securing  its food.    In this  case  also the tongue seems
longer than the body itself.
                             Fig. 371.
 Tongue of Common Fly.  a, Lobes of Lingula.  b, Portion enclosing the Lancets
formed by the Metamorphosis of the Maxilla,  c, Maxillary Palpi,  a, Portion of
one of the Metamorphosed Trachea; enlarged.
  How does the chameleon obtain his insect food ? 760. Have fishes any tongue, or tho
sense of taste? 761. How well is this organ developed in some of the lower animals?
762.  Describe the shape of the nose.  Of what is it principally composed ? 
412          Hitchcock's  anatomy.

  760. This sense in fishes appears to be very feeble.  " The
part named tongue  in them  consists merely of the anterior
extremity of the tongue bone  covered by mucous membrane."
If fishes possess this sense, the palate rather than the tongue
is probably its seat.

  761. Invertebrates.—Taste, doubtless, exists in all the
lower animals, else how could they select their food ?   The
seat of this sense is not always discoverable, as can be done
in the Cephalopoda.  But the sense exists in all, even in the
Protozoa.  Fig. 371 exhibits  the tongue of  the common fly,
which is doubtless the seat of this sense.
               SENSE   OF   SMELL.

       DEFINITIONS  AND   DESCRIPTION'S.

  762. Anatomy of the Nose.—The Nose, which contains
the organs of smelling, is a triangular pyramid placed upon
the face, its apex connected with the forehead, and its base
descending nearly to a level with the upper lip.  It is prin-
cipally made up of bone cartilage and integuments, having a
                              thin  plate  of bone (the vo-
                              mer)  and  cartilage in the
                              middle Avhich run in a verti-
                              cal direction, and  divide the
                              cavity into two portions called
                              the nostrils.  (Fig. 372.)

                                A View of the Cartilages of the Nose.
                              1, The Nasal Bones. 2, The Cartilaginous
                              Septum.  3, The Lateral Cartilages.  4,
                              The Alar Cartilages. 5, The Central por-
                              tions of the Alar Cartilages which consti-
                              tute the Columns.  6, The Appendices of
                              the Alar Cartilage. 7, The Nostrils.
 
AND  PHYSTOLOGY.
413
   762  a.   Use  of  the  Bones.—Use  of   the  Cartilages,
nnd  the   Glands  in  Integuments.— The  bones are the
two nasal, which give form to the base of  the nose, and fur-
nish a firm  attachment to  the muscles.   The cartilage  is of
use to give form to  the  nose, while  its elasticity lessens the
effects  of  injuries.   The integument or  skin  is  quite  thick
upon this  organ, and aids the cartilage  in giving form to it.
It contains in its substance small glands, which secrete an oily
matter to  protect the nose from extremes  of weather.   These
glands  are liable to retain dust and  other impurities in  their
orifices, forming the black specks on  the nose.
   763.  Lined  with Mucous  Membrane.—The  whole  cav-
ity of the nostrils  is lined with mucous membrane, Avhich is
continuous with the  lining  membrane of  the fauces  or  throat,
with which the nostrils are in communication.
   764.  Cavities of the
No stri Is. —Nerve  of
Smelling.—The  cavities
of  the  nostrils  are  very
irregular,  since upon their
own outer sides are found
the  turbinal  bones  and
a similar  scroll-like por-
tion  from  the  ethmoid
bone, for  the  purpose of
giving  as  large  a surface
as possible for the expan-
 A Vertical Section of the Middle Part of the Nasal Fossae, giving  a Posterior View of
the Arrangement of the Ethmoidal Cells, etc. 1, Anterior Fossse of the Cranium.  2, The
same covered  by the Dura Mater. 3, The Dura Mater turned up. 4, The Crista Ga'.li
of the Ethmoid Bone.  5, Its Cribriform Plate.  6,  Its Nasal  Lamella. 7, The  Middle
Spongy Bones. 8, The Ethmoidal Cells.  9, The Os Planum.  10, Inferior Spongy Bom-.
11 The Vomer. 12, Superior Maxillary  Bone. 13, Its Union with the Ethmoid.  14,
Anterior Parietes of the Antrum Highmorianum, covered by its Membrane.  15, Its
Fibrous Layer 16, Its Mucous Membrane. 17, Palatine Process of the Superior Maxil-
lary Bone.  18, Roof of the Mouth, covered by the Mucous Membrane.  19,  Section of
this Membrane.  A Bristle is seen in the Orifice of the Antrum Highmorianum.
  762 a. State the use of bone and cartilage in the composition of the nose. Of what ser-
v«ee are the little glands in its skin? 763. What are the nostrils lined with? 764. Do-
scribe the cavities of the nostrils.
 
414
HITCHCOCK'S  ANATOMY
 sion of the nerve of smell, and at the same time furnishing such
 an arrangement, that the air containing the odor can be readily
 drawn over it.   This nerve is  the Olfactory or first pair of
 cranial nerves, which,  as soon as  it reaches the nostrils, is
 divided  into a great number of filaments,  and these are  dis-
 tributed upon the mucous membrane —called Pituitary—al-
 ready described.   The fifth pair of cranial nerves  also  sends
 branches to  this membrane,  by  means of which  it is that
 sneezing is effected.
   765. Smell  under  the Control of the Wi 11 .—The sense
 of smell is somewhat under the control of the will, since  the
 air containing the odoriferous particles can be carried over the
 nostrils or rejected at  pleasure, and it can also be cultivated
 to a great extent, although some persons are  naturally more
 sensitive to odors than others.   It is related that a  gentleman
 who had a great antipathy to cats, could tell if  there was  one
 in the next room by  smell alone.  And the blind boy Mitchell
 always formed a  favorable or  unfavorable impression of a
 stranger by this sense.


        THE   SENSE  OF SMELL  IN  ANIMALS.

   766. The sense of smell is most perfectly developed in air-
 breathing animals, although many which live in the water, can
 distinguish odors or scents to a considerable distance.
   767.  Smell  in   Mammals.—In Mammalia  the mucous
 membrane  covering  the  turbinal  bones  is  supplied with  ol-
 factive nerves.   And in carnivorous animals,  like  the Lion
 fi.id Tiger, these bones are split up into several laminae, giving
 them arborescent or tree-shaped forms, so that the membrane

  AVhy are the turbinal bones placed here ?  What is the nerve of smelling? 765. To
 what extent is smell under the control of the will ? What curious facts in this connec-
tion ?  766. In what animals is this sense the most perfectly developed ?  767.  Among
what mammals do we find this sense in the greatest perfection ?   What peculiarity in
the turbinal bones in the lion ? 
AND  IHYSIOLOGY.
41_
may be expanded over as  great  a surface as possible.  The
cavities in the bones of the face and skull in these animals, as
Avell as also the Horse and  Deer, are very  much developed,
and  all the mammalia, except the Whale tribe, are supplied
with a turbinal  bone, the cavities  of which are  lined  by a
membrane which  greatly aids in the  sense of smell.  The
sense of smell  is also  greatly developed in the  timid grazing
animals, so that they may in this way receive notice of the
approach of their enemies and escape.  For most quadrupeds
give off a strong odor from their  bodies, in the exhalations of
the skin.
   768. Smell  in Birds.—A Nasal Gland.—Birds  possess
turbinal bones  and a large  nasal cavity,  but  it is  doubted
whether  much  of the poAver of discerning their prey de-
pends on  this sense, or whether it  does not entirely depend
on vision.   For  the  olfactory  nerve merely  ramifies  upon
a part of  the nasal cavity, the  remaining portion being sup-
plied  with branches  from  the  fifth  pair.   There is,  how-
ever, a peculiar  gland called  the nasal, which serves the pur-
pose of lubricating the pituitary (or mucous) membrane, which
is probably necessary from the fact  that so much air is con-
stantly passing over  the nostrils that the  membrane would
otherwise  become dry and thus impair the sense of smell.
   769. Smell in Reptiles— Reptiles seem by their organiza-
tion of very simple nasal cavities, to have their sense of  smell
feebly developed.  A few only have bony or cartilaginous
turbinal organs, and  a  portion only have  the  cavities  lined
by a pituitary membrane ; and from the  gormandizing habits
of these animals,  we see that the  sense of smell could be of
but little service  to them.
   770.  Smell in Fishes.—Fishes possess a cavity lined by  a

  What bone is the whale tribe wanting in ? How is the sense of smell in grazing ani-
mals »  768 How well developed are the organs of smell in birds? What is probably the
case with regard to their powers of smell ? What gland is furnished to them which pos-
sibly aids this sense?  769. What is said of this souse among reptiles? Is this sense  of
any great value to them ? 
116
HITCHCOCK'S   ANATOMY
pituitary membrane and furnished Avith olfactory nerves, which
gives them a powerful organ of smell.   This cavity, however,
has no posterior  orifice, its only opening being in  front, and
the water in it being continually kept  in motion by the ciliae
with Avhich  it is lined.   In the sharks and rays there is a mus-
cular appendage to  keep the water  in motion,  so that Sir
Richard OAven says these animals must actively scent (that is
search for odoriferous impressions) as Avell as smell.

   771. Articulata.—Crustaceans  have the sense  of  smell,
and the central ganglion sends off an  olfactory nerve.   The
Arachnoids can  smell  Avithout any  discoverable  organ.   So
also the Insects.   Probably all of the  Articulates have this
sense, but perhaps  Avithoat special organs.

   772. 31011U S C S.—In Cephalopods olfactory organs are made
out, but not in the other classes.

   773. Radiata.—No distinct organs for this sense have been
found in these animals.   But the presumption is that it exists
Avith or Avithout special organs in them  all.

   Of tbo Protozoa the Infusoria clearly evince sensation and
volition;  but no nervous  system has been discovered in them,
and though it is quite manifest that they are sensible  to the
contact Avith objects and to light, yet there is no evidence that
they have the sense of  smell.   Equally probable ii it that  it
is wanting in the Rhizophoda.
    HYGIENIC INFERENCES IN  RESPECT TO  THE  SENSES.

  774.—1. Moderation  in  their Use  Required.—All tli
organs of sensation require to be moderately employed.   If
 770. How is it with the sense of smell in fishes?  WTiat peculiarity among the sharks
and rays?  771. Have articulate animals the power of smelling? Have they the organs
adapted to it ?  How is it probable that lobsters smell ?  772. Can shell-fish smell ? 773.
What of animals lower in the scale ? 
AND PHYSIOLOGY.
41V
the eye be  used in too strong light, weakness or partial pa-
ralysis of the optic nerve may be produced ; and if  the ear
receive too violent  a sound, deafness may MIoav, and so with
the other senses.   Therefore care should be taken in the use
of  the senses, for  Avhen the  function  of one  of the nerves
of special sensation is gone,  it is very rarely if ever restored.
   775.—2.  Sudden Extremes of Sensations to be Avoided.
 —With  some of the senses,  and especially that of vision, great
care must be taken  to avoid, if possible, sudden transitions.
Next to very excessive use and mechanical violence, no greater
trial  can be given  to the optic nerve  than  a sudden contact
Avith powerful light.   To a  student  this  inference is of great
value, and especially to those  who would rise early and study
by candle-light, before daybreak.   This practice  is often a
source of confirmed Aveak eyes.   One  reason is, that during
sleep the pupil  is  dilated,  and when the  eye is opened does
not readily contract.   This statement, however, is not an ar-
gument  against early rising, which  for other reasons has been
shown to be healthy to the  student.   A good rule for students
in sound health during the long nights of the  year is to rise
before daybreak, and after washing the eyes in pue cold water
 to  take  a  good share of the exercise  needed  for the day.
 Then, after an  early breakfast, when food  and exercise  are
 both  obtained, he maybe ready for a day's work of hard study
 by the congenial light of the sun.   If, however, circumstances
 are such that Ave must study in  the  morning by lamp-light,
 we should  commence  and Avork  moderately until the eye is
 accustomed to the light.
   775.  a.—S.  Cleanliness of the Organs of Sensation Nee
 essary.—Perfection of sensation  requires that all the organs
 should be kept clean.   The eye needs occasional washing, not
 774  AYhy do the senses all require moderation in their use? What if a nerve of special
sense is destroyed ?  775. What is said of sudden extremes of sensation?  Why should
students especially avoid all extremes of light and darkness as far as possible ? How does
early rising affect the eyes? 775. a. How does cleanliness affect  all the organs of the
senses ? 
418
HITCHCOCK'S   ANATOMY
rubbing, with cold water ; the ear not only needs the applica-
tion of cold water, but occasionally the careful use of the ear-
pick to  remove  the accumulations of Avax Avhich is gathered
beyond the  reach of ordinary washing.   If  the nostrils are
buried by collections of snuff, how can Ave  expect acuteness in
the sense of smell ?
   776.—4. Senses Need Education.—The senses need edu-
cation.   No  portions of the body show so well the good effects
of discipline and practice  as  do  the  organs of sense.   The
power which, by training, can be acquired  of distinguishing
the faintest shades of color, the slightest discord between mu-
sical tones, and of the quality  and flavor  of food and drinks
by the smell and taste, is so great as to astonish us.
   777.—5.  Is  Taste a Proper Guide for the Appetite ?—
The question often arises whether the sense of taste can be
considered a safe  guide for the appetite.   As it is natural,
some maintain that it should ahvays  be gratified.  But even
if originally safe to folloAV,  Iioav often has it been perverted by
extravagant diet, and is at the time in  a morbid condition from
a perATerted state of the body ?   If such be the case, Ave should
be on our guard against indulging peculiar appetites, or strange
tastes.   But in some cases, of Avhich the physician is the best
judge, it may be  safe  to allow a reasonable  indulgence in a
desire for a peculiar article of food or drink.
   778.—6.  Our Senses Sometimes become  Sources of Mis-
ery.—In such a world as this our senses,  especially if exqui-
sitely cultivated, often become inlets of keen suffering.   Ob-
jects  disgusting to the soul must necessarily obtrude themselves
upon every one.   Those who are afflicted Avith a dainty appe-
tite  and are very nice  and particular as to their food,  often
suffer acutely ;  Avhile  he Avho has  learned  to  eat  only that he
may live, instead of living only that he may eat, experiences
j           776. Do the senses show the good effect of education ?  777. Is taste a sufficient guide
         for the appetite?  What is said of peculiar appetites and tastes?  77S. Doonr6ensesever
i         give us pain ?  In what way does a cultivated taste often make us wretched? 
AND  PHYSIOLOGY.
419
gustatory enjoyment from the same food that turns the stom-
ach of another.   True, a taste for the fine arts must be culti-
vated,  although  the sensorium will thereby be subject to pain
from discords in sounds, and incongruities in colors and forms.
But in respect to diet, regimen and  manners  it is hazardous
to cultivate the sensibilities till Ave become disgusted  with al-
most every thing Ave meet, and make ourselves objects of ridi-
cule for our peculiarities.
   779.—7. A  higher  kind of  Happiness  than that  de-
rived from the  Senses.—Finally, we ought to remember that
enjoyment gained through the senses, is not the highest kind of
happiness for man.   Thou h it be all, or nearly so, which the
brute can enjoy, yet the intellectual and moral powers of man
demand of him  the  control of his sensual desires, and  a love
for that AA-hich is far higher and  purer,   For  thus will all his
faculties be engaged in  their appropriate sphere, and  keep
bright till  the end  of life, and as its  evening shadows steal
upon him,  they  will find  him not  full  of disease and Ioav de-
sires, but peaceful  and  happy, ready to make a change from
bodily to  spiritual  realities, almost without a sigh and'with
exulting anticipations.
T79. Is sensual happiness superseded by no higher enjoyment? 
CHAPTER    NINTH.
 RELIGIOUS  INFERENCES  FROM ANATOMY  AND
                     PHYSIOLOGY

   780.  Highest Use of Science.—The  highest  and most
important use of all science, is its religious applications : since
these are eternal, while all its secular bearings are only tem-
poral.
   781. Religious  Value  of Anatomy and  Physiology.—
Perhaps no sciences are so prolific of religious applications as
anatomy and physiology.  They bear especially and almost
exclusively upon Natural Religion.


    I. PROOFS  OF  THE  EXISTENCE   OF  GOD.

   782. The argument for a Deity from marks of design so
obvious in nature, derives some of its most striking examples
from anatomy and physiology.
   783. The Eye.—The eye has often been quoted as a strik-
ing instance.  Who  can  mistake  its object ?  And when we
examine its structure, we see how admirably adapted all  the
parts are—the coats,  the media, and the nerve—to secure this
object.   And it is done  far more perfectly than by the finest
optical instrument of man's construction.
   784. The Ear.—In the ear  we  have another example al-
most equally striking, except that the special object of some
of its parts is not so obvious as in the eye.
   785.  Hands. Lungs,  Heart,  etc.—We  might say  the
same of the hands  and the feet, the lungs, the muscles, the 
          ANATOMY   AND   PHYSIOLOGY.       421

nerves and the heart.   If design  is not manifested in their
construction,  it is difficult  to  see how it  could  be mani-
fested.  The  mechanical arrangements and operations  of the
different parts of the system teach the same lesson.

  786.  Skeleton.—Spinal Column.—Take the  bones of the
skeleton for an example. How admirably are these arranged as
a solid framework, around which the soft parts of the system
may be built up !   The  vertebral  column  is not a single
straight tube, as our wisdom Avould probably  think  to  be the
safest and best as a protection to the spinal  cord within, but it
is made up of over thirty bones separated  by an  elastic sub-
stance, yet locked together and  fastened by strong ligaments,
so as in fact to be stronger than a single piece, and  moreover
it is made somewhat crooked,  so  that  it  will yield  a little
when jarred,  and thus prevent the brain from being  injured.

  787. Joints.—The joints too, how  admirably fitted for the
manifold movements we  need to make!  How securely fastened
together  by numerous strong ligaments !  How  much more
effectually lubricated by the synovial fluid  than the  most per-
fect engine of human construction !   Then  again,  how exactly
fitted to  the parts of the body, in which they are placed, are
the  different kinds of joints, the  ball and  socket, the  hinge,
the  sutures, etc.  !

  788.  Muscular  Arrangement.—Their  Mechanical Dis-
advantage, etc.—Contraction.—Perhaps  even more striking
are  the character, position, and mode of action of  the muscles.
Always in pairs, except  where a single one is all that is needed;
being antagonistic only Avhere antagonism is wanted; being thic £
where great strength must be exerted, or some cavity must' 9
filled to  produce  symmetry of  form;  being thin  where wide
surfaces were to  be covered, or a proper  proportion  could not
be secured between the different parts of the body.  Then how
wonderful  that the  great mechanical disadvantage, at which
muscles act, which at first  sight seems  so obviously a defect 
422
HITCHCOCK'S   ANATOMY
of arrangement, should  on reflection be found wisely adapted
to our wants and comfort.  The mode  in which the muscles
act by mere contraction,  is the simplest  possible ; yet Avhen Ave
inquire how this is effected, Ave find ourselves in contact with
some of the profoundest and most  difficult of all subjects:
there is not only design,  but unfathomable wisdom here.

   789. Harmony  of Chemical  and Vital  Agencies— The
conjoint operation of chemical and vital  agencies in building
up and perfecting the system, and freeing it from impurities,
is another  marked example of design.   These  agencies, the
chemical especially, are blind, and Ave might expect that they
would as often destroy as they would preserve.   But though
they are incessantly at work all over the system,  as if it were
a busy laboratory, in  building up the  tissues, in converting
elements into immediate principles,  and in  separating and
casting out of the body the superfluous and deleterious  mate-
rials, all goes right till Providence permits disease or accident
to disturb the harmony  between vitality and chemistry, and
from  the disastrous  effects of their morbid  action, we learn
hoAV  Avisely ordered was their healthy operation.

  790. Special  Arrangement  exhibiting  Design. —There
are some special contrivances and arrangements in the animal
frame, which strikingly  show design, because it looks  as  if
the Author of Nature had made a modification of his plan
to meet exigencies.   Take a few examples.

  791. Looped Muscles. —Look   at  the  looped  muscles.
There  the  tendon  is fastened by a loop, in order  that  the
direction of the force, applied in contracting  the muscle, may
be more or less changed, made in some instances, as in  the
oblique muscle of the eye, to pull in an opposite direction ;
or at right angles, as when the digastric muscle draws  down
the chin.

  792. \nastomosis of  Blood-Vessels.—Then  there  is  the
inosculation of the  blood-vessels.  How obviously this  is in- 
_.ND  PHYSIOLOGY.
423
tended as  a security, when some  of  the blood-vessels  are
wounded and can not transmit the blood.   It then seeks those
side channels, and soon they so enlarge  as to give free passage
to all the blood that is needed, even though a large vessel has
been closed.  If man  had constructed a machine Avith such an
arrangement we should have been sure Avhat Avas  the  design.
Why doubt the same in respect to God's work ?
   793. Protection of Large Vessels.—Again,  the large
olood-vessels and nerves are placed  deep in the system, and
where they pass by prominent joints,  grooves, or tubes, are
made  for them; or where one side of a joint is exposed  to
injury and the  other comparatively  secure, the important ves-
sels are grouped together on the less exposed side, as in the
groin and arm-pit.
   794. Annular Ligaments.—Take,  for another example,
the annular ligaments around the wrist and ankle.  Who can
doubt that they were placed there to prevent the tendons  of
the muscles from starting out of their  places, when the mus-
cles are strongly contracted and the feet and hands bent ?   If
so, who can doubt that a Being of infinite wisdom devised and
executed this arrangement ?
   795.  Nervous Power .—But all  this wise disposition of the
parts of the body might  have been  made and  yet  the whole
have been useless,  had not some vivifying force  been added.
Therefore  the nervous system was contrived and  incorporated
with every part of the body, commencing with the brain and
ramifying  to all the extremities.   It needed, too, a central
 power to°direct and control the nervous energy, and therefore
 the mind, an immaterial and immortal principle, was enthroned
 m the brain.   From thence,  as along  so many conducting
 wires, and doubtless  by means of galvanic agency, it sends out
 its orders  to originate and control  every muscular movement
 and keep  in play every function of the  body.   The  nervous
 system, then, is the mysterious connecting link between mind
 and matter, and the admirable manner in which it performs its 
424
HITCHCOCK'S  ANATOMY
functions and enables the thinking principle to manifest its
astonishing powers, shows the nervous system to be  the  most
wonderful of all  the contrivances which Infinite Wisdom has
placed in the human body.   What could demand an Infinite
Deity if such a contrivance did not ?
  796. Dependencies of one  System upon Another.—The
connection  between mind and body, however, is only imper*
fectly understood, and therefore there is one other thing whic_L
exhibits more impressively than the nervous system and the
mental powers the agency of an infinitely wise Being.   The
human body is made up  of quite a number of minor systems
of organizations  apparently independent of  one another, yet
all in fact mutually dependent and combined into one complete
and perfect system, with the parts all exactly adapted to one
another.   Could any thing less  than Infinite Wisdom  have
accomplished so marvellous a work ?
  797. The same Plan  Exhibited in  the whole Animal
Kingdom.—Yet if we extend our researches through the whole
animal kingdom, Ave shall find that this same mutual adapta-
tion and correlation extend  through the whole series, so  that
all are but parts  of a mighty Avhole.   From  man downwards
through the hundreds of thousands of species, to the humblest
animalcule, each occupies a  fitting place, and every link of
the long chain is in perfect harmony with all the rest, so that
the skillful anatomist, knowing  one part of the chain, can
delineate the rest, just as a  single bone of  an animal often
determines  the character of its whole  frame.   What   vast
reaches of thought, what wonders of wisdom,  what boundless-
oess of power must it have required, to weave together so vast
and varied a system into one  golden web  of harmonies !


  II.  PROOFS  OF  DIVINE BENEVOLENCE

  798.  All Organs  and  Functions  Normally  Produce
Happiness.—One proof of Divine benevolence is, that all the 
AND  PHYSIOLOGY.
425
organs and their functions are adapted to promote the welfare
of the individual.  They may incidentally result in evil;  but
the object was to produce happiness.   One  object of the ner-
vous system Avas to guard us against injuries by putting us
on our guard against them.   But in case of injury or diseased
action, intense* suffering often results  ; and while enduring it
we  are apt to forget the grand object  of the nerves of sensa-
tion, and imagine incidental to be intentional evil.   So carni-
vorous teeth and poison fa>:gs are intended  to provide animals
with food and the  means of defense.  But they may produce
great incidental  evils by being used as animals have the power
to do, and are sometimes incited to dov aside from the normal
objects for which they were given.  Indeed there is no organ
or operation Avhose leading object is not the production of hap-
piness ; and therefore we infer the predominant disposition of
the Author of nature to be benevolent.

   799. Pleasure Superadded  to Functions when  not  Re-
quired.—A second fact leading to the same conclusion is, that
often pleasure is superadded to animal functions, when it is
unnecessary to their perfect performance.  It was not neces-
sary  to  perfect vision that  the colors in nature  should be
agreeable ; that the  earth, for instance, should  be green, or
that colors in flowers should be harmoniously blended.   It
was not necessary for the  support of the system  that gusta-
tory enjoyment  should accompany the  reception of food; for
severe hunger would have been sufficient to impel us to  eat,
even though suffering followed.  And so in a thousand other
instances that might be named.   On the other hand, no exam-
ple can be  founl where unnecessary pain attends functional
operations.   The Author of such a system must be benevolent.

   800. More  Modes than One Provided for the same Func-
tions ,__A third evidence of benevolent design in the Author
of the animal system is the provision often made of more than
one mode for the performance of important functions.  In the
act of swallowing, for instance,  the danger is great  that  pais 
426
HITCHCOCK'S  ANATOMY
tides of food may pass into the lungs.  Hence not only is the
epiglottis  provided to close  upon the  glottis like a valve by
the very movement that carries down the food ;  but the glottis
itself is endowed Avith such extreme sensibility that it instantly
closes upon the approach of a foreign body.  The inosculation
of the blood-vessels has already  been described, furnishing  a
double means of circulation as a resort Avhen  one fails.  We
might also refer to the two cerebral  hemispheres,  tAvo lobes to
the lungs,  two eyes, two hands, and two feet, so that the loss
of one does not obliterate the function.   All  this  certainly
looks like the benevolent provision of a  kind  parent.
   801.  Surplus or Reserve Power.—And  so, in the fourth
place, does the surplus power given  to the organs for exigen-
cies  above Avhat is necessary exhibit benevolence.   In the
muscles there seems to be no limit to this excess of force, save
in the ability of the fibers to endure  the strain.   The digestive
organs are capable of mastering a much larger amount of food
than is necessary, and the secretory  organs at  times give out
a much larger than the normal quantity of their peculiar prod-
ucts.   If it were not so, life would be sacrificed in thousands
of instances Avhere now the use of the surplus power preserves
it.  If God is not benevolent how happens it that this special
provision for exigencies should always promote the welfare of
animals ?
   802.  Vicarious Power.—In the  fifth  place, the vicarious
power given to some of  the  organs  teaches  the same lesson.
When one or more of the senses is destroyed  or  defective, the
others  can often,  in a  good measure,  supply their place :
touch,  for instance, the place of seeing  and hearing.  So
also, it is said Avhen tho glands appropriated to certain secre-
tions are injure 1 or destroyed, others Avhose  normal secretion
is quite different, can elaborate the principles ordinarily given
out by the injured ones.
   803.  Adaptation of Organs to Different Circumstances.
—The power of all the organs to  adapt  themselves to different 
AND  PHYSIOLOGY.
427
circumstances is a sixth example of benevolent intention in the
Author of nature.   The range of this power is limited; and
yet Ave are often surprised to Avhat Avidely different conditions
we can be accustomed, and yet be comfortable in them by new
habits.   In such a changing world as this is, such  a power
seems almost indispensable, and  yet  only infinite skill could
attach it to  organs which are controlled  by inflexible chem-
ical and vital laws.   Malevolence surely  never Avould have be*
stowed it.
   804. Recuperative Power.—The recuperative  power of
the animal system  furnishes  us  with a seventh example  of
benevolent provision by the Creator.  However deeply acci-
dent or disease may have affected the system, if the vital pow-
ers be not destroyed, it is possible frequently to bring it back
a^ain to a state as  sound and  vigorous as before. The records
of pathology and surgery furnish  most astonishing  cases of
such restorations.  And since accident and disease are so com-
mon  that scarcely any adult  can boast of immunity from
them,  what a sad picture would society present of cripples and
invalids, Avere this  recuperative power wanting.   It Avould be
 just  such a  picture as infinite malevolence  would delight  in.
 Its opposite therefore indicates benevolence.

   805.  Prospective Benevolence.—One other example only
will be given, and that may be called prospective benevolence.
 Wasps and some other  insects  have an instinct Avhich leads
 them to deposit along with their eggs a  supply of food for the
 young  insects when they are  hatched,  sufficient  to nourish
 theintill they are  old enough to take care of themselves.  In
 other animals nature  provides a supply of milk to  be ready*
 just  at the  time Avhen needed by  the  progeny.  The adult
 man needs a firmer set of teeth than the in ant, and so  the
 germs  of these  are placed beneath the earlier teeth,  and these
 at the proper time  push their way  upward, and crowd  the
 first  set out of their sockets.  In  such cases  the  wants of
 animals were  anticipated hy their  Creator, just   as a  be- 
428          HITCHCOCK'S  AN'ATOMY

nevolent parent provides beforehand for the future needs and
happiness  of his children.

  806.—III. ANATOMY  AND  PHYSIOLOGY  FURNISH  PRE-
SUMPTIVE  EVIDENCE THAT  THE  AVORLD  IS  IN  A  FALLEN
CONDITION.

  807.  Benevolence blended  with Pain.—We have showr
that benevolence decidedly predominates  in all the organiza-
tion and functions  of the animal system.   But it is not un-
mixed benevolence,  as we shall now attempt to show.  There
are evils connected  Avith our physical condition, such as Ave
can not  suppose would exist in a paradisaical state, and  the
inference is that these evils are best accounted  for by the sup-
position  that the world is adapted rather for a fallen than for
a holy being.  Let  us look  at  some examples of evils which
we  can  not suppose a  Being of Infinite Benevolence and
Power Avould connect with a state of perfect holiness.

  808.  The Nerves much  more Sensitive than is neces-
sary to Protect.—1. The nervous system produces suffering
far beyond what is necessary, to put us on our guard against
accidents  and  injurious agents.   To  aAvaken  and  cultivate
such prudence in respect to these evils, seems  obviously  a
leading  object  of pain and suffering:  for the nerves are most
abundant  and  sensitive at the  surface of the  body.  But in
many diseases the suffering  is intense.  Indeed, exasperated
and maddened  nerves produce  the very climax of human
anguish.  But  some other object  besides aAvakening a salu-
tary caution against  evil  must  be  in view by such suffering.
Now Ave knowr, that as a matter of discipline  for a depraved
and sinful being,  it  is eminently salutary.   It affords there-
fore a presumptive proof that such is man's character.

  809.  Impossibility of avoiding Accidents and  Disease
—2. Man's exposure to  accidents and diseases, which no
human foresight can avoid, leads to the same conclusion. 
AND  PHYSIOLOGY.
429
   810.  That he is thus liable, we need not attempt to prove,
 because all will  acknowledge it.   But  why should he be so
 exposed under the government of a Being of Infinite Benevo
 lence, if there were not something in his character which de-
 manded this severity of discipline ?   What can that be but an
 alienated, rebellious heart, which no milder means will subdue?
   811.  Evil incidental  to every Function.—3.  Evil is
 ncidental to the functions of every organ in the body.  Vision
 exposes  us to be Avitnesses of many most unpleasant scenes
 and objects, hearing  to sounds most  grating, taste  and smell
 to  odors and solids disgusting  and poisonous;  locomotion
 makes us liable to fatigue and bodily injuries, and disease es-
 pecially assails every organ.  We can not conceive these in-
 cidental evils to be necessary in a world of perfect purity and.
 happiness.   But they are wisely adapted to a fallen being, and
 therefore the presumption is that  man is in such a fallen state.
   812.—Universality  of Death.—4. The existence and  uni-
 versality of death lead to the same conclusion.
   813. It may indeed be made probable that in such a stat.
 of things as the present, death is a blessing even to the  inferior
 creatures.   But it would  not be so in an unfallen paradisaical
 state.   It  must be an immense drawback from the  happiness
 of such a state.   It is, however, a fit and probably an inevit-
 able concomitant  and consequence of sin.   Where it is uni-
 versal, therefore, the presumption is that it is a fallen state.
  814.  Condition of Man  not without Bright Prospects.
■—5. But though anatomy  and physiology present so many
proofs of man's fallen condition, yet the evidence alreadv ad-
duced  that  benevolence  vastly  predominates,  affords to the
p'udent of natural theology a strong presumption  that it is
not a hopeless condition.  For if there  was no such thing as
recovery, why so many tokens  of kindness ?    Why not give
up the offender at once into the hands of j ustice, and  let the
work of retribution commence ?   How the recovery might bo
effected revelation alone could show. 
4:10
HITCHCOCK'S   ANATOMY
  Objection.— It is said that these arguments would prove the inferior animals, even thoso
that lired long before man, to be in a fallen condition, since they both suffer and die.
  Answer.—The lower animals, not having a moral nature, cannot sin; but they may
Buffer in consequence of their connection with sinful man. The world, from the beginning,
was adapted to him as a fallen being, and of course aU other animals must be subject,
like him, to suffering and death.  This sympathy of all nature with man's fallen condition
is clearly taught in Revelation.  (See Rom. viii., 18-23.)
815.--IV. ANATOMY AND  PHYSIOLOGY FURNISH  PROOF OF
                     THE DIVINE  UNITY.

   That  is, they show that  only  one  Mind could  have  been
concerned in the plan of animal organization.
   816.—1. The Conspiration of all  the Parts  to  Produce
the Same  End.—This  appears, in the first place, from the
conspiration of all the  tissues and organs to produce  a single
result.   There  are as many as a  million of parts  in  the  hu-
man body, all of Avhich must go right to keep the system in a
healthy state,   it  may worry us Avhen some of them go Avrong,
as in case of disease; but if many of them become deranged
death ensues.    An attentive observer  of the race will  see that
all these parts  are  originally arranged so as to conspire in the
production of health and happiness.   There  could have  been
no divided counsels in such a work.
   817.—2. Relations  of  Different  Individuals  in   the
Animal  Kingdom.- The relations of all the branches and even
individuals of the Avhole animal kingdom to one  another af-
ford a still more striking evidence of divine unity.   For here
the objects to be compared are  multiplied a thousand fold, and
the extremes in organization,  in  habits, and modes of living
are immeasurably Avide    Yet  there is sucb a relation among
them all as to show them all belonging to one system, bound
together in the  closest harmony.   All  must, therefore, hava
been  the work of one  Infinite Mind.    Or if more than one
was concerned, each must have had  the same plan ;  and  the
idea is absurd that  there can exist more than one  infinite
mind. 
AND  PHYSIOLOGY.
431
 818.—V. ANATOMY AND PHYSIOLOGY  DISPROVE  THE ATHE-
    ISTIC HYPOTHESIS THAT THE DEVELOPMENT  OF ANIMAL
    ORGANS  IS THE RESULT OF  MERE  LAAV.

   819. The  Development Hypothesis.—This hypothesis sup-
 poses that the organs Avere not contrived and constructed by
 an intelligent mind for the uses to Avhich they are applied, bub
 that the wants of the living mass of almost amorphous matter
 led to such efforts as ultimately to form an organ.    Thus the
 desire for food in a  mass of vitalized jelly caused  it to pro-
 trude certain points which ultimately became hands, and the
 desire of  locomotion formed the feet and legs.  To form the
 organs in this manner it would be  necessary that  the  use of
 parts of the  living unorganized  mass or body should  have a
 natural tendency to produce them.   If  then we can show that
 in some cases this tendency Avould be exactly the opposite, the
 hypothesis must fall.   We need  give only a few examples to
 show  that such is the case.   Take the looped muscles, such as
 those in the back of the eye.  Any effort of matter behind the
 eye to move  the  ball must  draw in a direct line,  not in the
 round about course of a loop attached to the orbit.   Take the
 case of the annular ligaments at the wrist  and ankle.   The
 conatus of the muscles to move the fingers  and  toes would
 tend to destroy but not to form such a ligament.   They are as
 obviously intended as any thing can be  to counteract the con-
 atus of the tendons to fly off when the muscles contract.
   820. Such facts so manifestly show the  absurdity of the
 hypothesis under consideration,  that examples  need not  be
 multiplied.   It is true of nine tenths of the organs, that an
 effort  of vitality to perform their functions before their exists'
ence Avould have a tendency the opposite of their formation.
                            19 
132
HITCHCOCK'S  ANATOMY
 821.—VI. ANATOMY  AND PHYSIOLOGY  SHOW THE UNREA<
   SONABLENESS OF OBJECTING  TO MYSTERY  IN RELIGION.

   822. Any objection against religion that will lie with equal
 force against the constitution and course of nature is  futile.
 For none but the atheist will deny that nature is the work of
 God, and it  is  not reasonable  to object to  that in religion
 which we alloAV to  exist in nature.  But the cases of mystery
 in anatomy and physiology are more striking than in religion.
 A few examples Avill suffice.
   823.—1. Muscular movement.   We can see that muscles
 contract, but the power that does it is concealed.   We  find
 that this power comes from the brain through the nerves;  but
 this does not show  us  how the work  is done.   We  find  that
 electricity is concerned ;  but why should electricity contract a
 muscle more than a wire ?   This carries us  to the end of our
 knowledge, and still we  know nothing  of the nature of  that
 force by which the  will is able to move a muscle.  The Avhole
 range of science gives not the slightest clue  to the mystery.
 It is, in fact, as profound as any in natural or revealed relig-
 ion,  and until we can solve this we have no right to object to
 any  religious doctrine on the ground of mystery.
   824.—2.  The entire connection between  mind and matter
 teaches the same lesson.   When we have stated the facts as
 to their mutual influence, we have nearly reached the limit
 of our knowledge  of the subject.  There is no physical  law
 or mental law either that can  explain their action  and reac-
 tion.   All attempts to do this amount to little more than the
 vaguest hypothesis.   Any thinking man who studies the phe-
 nomena will  be impressed by the mystery that hangs over
 them, and if he be  a true  philosopher will  be slow to  reject
any doctrine of religion because it has depths in it which he
ean not fathom. 
INDEX    AND   GLOSSARY.
The numbers refer to the page.
                   A.
Aboma'sum, 186, 1ST.
Abdom'inal muscles, 125.
Abdom'inal aorta, 211.
Abdu'cent nerves, 329.
Acule'phi, one ol  the  groups of.  radiate
  animals.
Access'ory heart, 233.
Aera'ti'm, purifying by air.
Afferent, carrying to.
After tastes, 409.
Air, amount used in breathing, 253.
 "    »     of in lungs, 256.
Albu/men, a proximate  principle, 12.
Albu'minose, 12.
Algae, sea weeds.
Ambulatory, pertaining to a walk.
Amor'phous, without shape.
Amphiarthro'sis, 66.
Anastomo'sis, 202.
Anat'omy, definition of, 5.
    "      Comparative, definition of, 6.
An'chylosed, grown together.
Atifractuos'ities, depressions on the brain.
Angiol'ogy, 201.
Angular motion, 63.
Animal heat, theory of, 253.
   "   kingdom, classification of, 84, 85.
Animal'cules, minute animals.
An'nular, like a ring.
    "      ligaments, 132.
Antisep'tic, preventive of decay.
Aor'ta, 206.
   "•   in animals, 231.
A'pex, point or summit.
Aponeurosis, 110.
Appendages of cells, 18.
A'queous humor, 374.
Aquiferous, water bearing.
Arach'noid membrane, 324.
Ai'senic in the body, 7.
Arterialization—see Aeration.
Arteries, 204.
    "   and veins, comparative  capacity
  of, 223.
Arthro'di;i, 67.
Articula'ta, 85.
    "     skeleton of, 103.
Artic'ulate, to make a joint.
Artioula'tion8, joints.
       «        varieties of, 66.
       <*        anatomy of, 67.
Assimila'tion, conversion of matter  into
  the substance of the body.
Atmospheric pressure in joints, 71.
Audi'tion, hearing.
AuMitory nerves, 329.
Au'rielcs, 201.
Automat'ic, acting apparently without tha
  will.
Ax'illary artery, 206.
Azot'ic, containing nitrogen.
Az'oiised, containing nitrogen.

                   B.
Back Board, 144.
Basement membrane, 17, 298.
Beaded, like a string of beads.
Bc-lief, eflFect of on sensation, 36S.
Belly of muscles, 109.
Benevolence, Divine, shown by anatomy,
             424.
      "      prospective shown in organs,
             427.
      "      blended with pain, 428.
Biceps muscle, 119.
Bicus'pid teeth, 54.
Bile, 16, 175.
Bill of birds, 96.1S9.
Birds, rate of flight, 154
Blaste'ma, 20.
Blood, 15, 220.
   "   of articulates, 241.
   "   vessels, their use, 222.
   "      "     "   large amount, 22S,
Body, its size, 10.
Bones, chemical composition of, 31.
   "   mechanical structure of, 32.
   "   classes of, 85.
   "   strength of, 32.
   "   microscopic structure of, 33.
   "   intermaxillary, 89.
   "    jugal, 93.
   "   cor'acoid in birds, 96.
   "   sternal  "   '•   96.
   "   tarso-metatarsal, in birds, 97.
   "   sesamoid,       "  "    97.
   "   development of, 36.
   "   number of, 37.
   "   uses of, 74.
   "   distorted, reason of, 81.
   "   effect of wrong position on, S&
   "   hollow in birds, 9S.
Brachial artery, 206.
Bra'chial plexus, 334. 
434
IVOEI  AND  GLOSSARY,
Brain, 318, 342.                            |
  "   of mammals, 357.
Breathing, object of, 253.
Bronchi, 250.
   "     of mammals. 270.
Bronchi'tis, inflammation of the Bronchi.
Brunnei's glands, 163.


                    c.
Ccecal cells, closed  or shut sacs.
Ciecum, 161.
Calca' reons, hard like limestone.
Cal'cified, made hard like limestone.
Cal'cium in the body. 7.
Calisthenics, 141.
Callos'ities, 311.
Calcutta, blackhole of. 266.
Calorific, heat producing.
Canalic'uli of bones, 3-3.
Ca'nine teeth, 54.
Cap'illaries, 214.
Car'apaee,  99.
Carbon in the body, 6,
   "    its  amount  given  off from  the
  lungs, 255.
Carbon'ic aoid in the body, 10.
Carniv'orous, flesh eating.
Caiot'id artery, 206.
Carpus, 59, 78, 91.
Cartilage, invertebral, 42.
Cartilag'inous, made of cartilage,
Ca'sein, 12.
Caudal heart, 238.
Cells, 18.
  "   vital force of. 21.
  "   chemical changes of, 21.
  •'   vitalization of, 21.
  "   change of form, 21.
  "   periods in the life of, 21.
Cellular, having cells.
Cemen'tum, 51.
Centrip'etal and centrifugal, 349.
Ceph'alopsd, a molluscous animal.
Cerebellum, 319, 347.
Cer'ebral ganglia, 321, 343.
    "    hemispheres, use of, 841
    "    nerves, 35S.
Cer'ebro-spinal center, 322.
Cer'ebrum, 31S.
     "     of mammals, 857.
Cer'vical plexus, 334.
Chem'ical elements of the body, 6.
Chem'istry and vitality combined  show de-
  sign, 422.
Chi'tine, 84, 314.
Chit'inous, containing chitine.
Chlorine in the body, 7.
Cho'roid coat, 371.
Chyla'queous fluid, 241.
Chyle, 15, ISO.
Choles'terine, 11.
Chyme, 175.
Cil'ia>, minute hairs.
Cil'iary processes, 371.
Circle of Willis, 210.
Circulation in molluscs, 242.
     "      in  radiates, 243.
Circtunduc'tion, 68.
CUv'icle, 57, 78, 96.
Clca'ca, a sac appended to the intestines.
Ccag'ulable, cs~iia "f hardening.
I Coats of tho eye, their use, 37S.
. C„v_'lea,  391.
 Coc'cyx, 41.
 Cceliac axis, 212.
 Colds and Coughs. 263.
 Colon, 102.
 Color blindress. 3 5!
 Compound eyes, 3m!
 Cona'tux, attempt.
 Con'ditnents, their use and abuse, 1S4.
 Con'dyle, elevation or eminenco on a bona
 Convoluted,  rolled  together like  a tube.
 Coordination, working or  designing  t<*
    gether.
 Copper in the body, 7.
 Cor'acoid bone, 96.
 Coria'ceous, like leather.
 d/i-ium,  293,306.
 Cor'nea, 370.
 Cor'neous, like horn.
 Cor'pora stria'ta, 322.
 Cor'pusclex, little bodies or cells.
              of blood, 220, 228, 254.
 Corpulence, its effect on capacity of  lungs
    254.
 Corpus callosum, 319.
 Cra'nium, skull.
 Cra'nial nerves, 325-331.
 Cre'ation, 9.
 Cric'oid cartilage, 260.
 Cruxta'ceans, animals like the  crab and
    lobster.
 Ctenoi'dians,  314.
 Cubical size of the bodv, 10.
 Oune'iform cartilage, 200.
 Cuta'neoux, relating to the skin,
 Cu'ticle, 296.
 Cycloi'dians, 314.
 Cytogen'esis,  cell production.


                    D.
 i_aily water bath, 310.
 Daltonism, 383.
 Death universal, 429.
 Decuxsa'tiun, crossing like  an X.
 Deglutition, 172.
 Deity, argument for, from anatomy, 420.
 Den'tine,  51.
 Denti'tion, appearance of teeth.
 Den'izen, an inhabitant.
 Dermatol'ogy, science of the skin.
 Dermis, skin.
 Development hypothesis, argument against,
   431.
 Development hypothesis, disproved by an-
    nular ligaments, 431.
 Diarthro'sis, 67.
 Di'aphragm, 124,150.
 Dias'tole, 226.
 Diet best  adapted for man, 177.
 Digas'tric muscle, 116.
 Diges'tion, its theory, 174, 175.
 Dip'loo of cranium,  76.
 Disussimila'tion, process of wast*.
 Disease not to be avoided, 428.
    "    of circulatory organs, 228.
 Dorsal vessel, 239.
 Duode'nal glands, 163.
 Duode'nnm, 160.
 DupHca/tive folding or doubling.
 Dura mater, 323. 
INDEX  AND  GLOSSARY.                  435
                   E.
Ear, 889.
  "  a proof of design, 420.
  "  functions of all its parts, 394, 397.
  "  of animals, 297, 399.
Eating, hygienic inferences from, 183, 1S4.
Echin'oderms, radiate animals.
Efferent, carrying away from,
Electrical organs of fishes, 36J.
Elemen'tary tissue, 14.
Emacia'tiou, wasting away.
Enam'el, 51.
Enarthro'sis, 67.
En'dosmose, 17.
Eoider'mis, 296.
     "      use of, 305, 306.
Epider'mic scales, 311.
Epiglot'tis, 261.
Epithe'lial, relating to the epithelium.
Epithe'lium,  outer surface of mucous and
   other membrane.
Esoph'agus, 157.
     "     of horse, 1S6.
Eusta'chian tube, 891.
Evil incidental  not intentional, 425.
   "    «      to e,Tery function, 429.
Excrementi'tious, waste or superfluous.
Ex'osmose, 17.
Extremities, anterior, of quadrupeds, 92.
Exuda'tions,  15
Exuvia'tion, casting off.
       "       of serpents, 313.
Eye, anatomy of. 369.
   " a proof of design, 420.
Eyebrows, 376. 380.
Eyelids, 376, 330.
Eyes of mammals. 3S3.
   "   "  birds, 3S4.
   "   " reptiles, 335.
   "   " fishes, 3S0.
   "   "  insects, 336.
   "   '•  mollusca, S^3.
   "   "  radiata, 3S3.

                    F.
 Fac'et, a little surface or face.
 Face, 47.
 Fa'cial nerves, 329, 351
 Fats in the body, 11.
 Feathers, 312.
 Fel'on, 35.
 Fem'oral artery. 212.
 Fe'mur, 63, 79," 97, 100.
 Fever sore, 35.
 Fiber, simple, 17.
   "   muscular, 107.
 Fi'bril,     "    107.
    "  in contraction, 137.
 Fibrin,  12.
 Fib'ula, 03.
 Flu'orine in  the body. 7.
 Fol'licles, 2S9.
     "     of Lieberkuhn, 163.
 Food, for what purposes required, 176.
 Foram'ina of bones, 35
 Forces of blood circulation, 223, 226.
 Fore  arm. 53. 78.
 Fright, effect of on hair, 315.
 Fnintal bono, 43.
 Functions, the mode for their performance,
   425
 Fu'siform, spindle shaped.
Gall-Bladder, 165.
Gang'lia, small knots or masses of nervoui
  matter.
Ganglia, uses of, 350.
Ganoid'ians, 314.
Gastric juice, 15, 173.
   "   follicles. 159.
   "   artery, 212.
Ge'n us, a group of species.
Gills of Fishes, 274.
Gin'glymus joint, 67.
Giz'zard, second stomach of fowls.
Glands, their anatomy, 2S9.
   "    ductless, 292.
   "    of the skin in mammals, 312.
Gliding motion, 6S.
Glob'ule, spherical particle of matter.
Glob'ulin, 12.
Glosso-pharyngeal nerves, 830, 351.
Glu'ten, 12.
Glu'teus muscle, 123.
Gompho'sis, 66.
Granules of cells, 13.
          " bone, 34.
Gymna'sia, their use, 141, 144.
H.
Habit, effect of on sensations, 368, 402.
Hair, number and distribution of, 803.
  "   clicmic.il  composition of, 303.
  11   constitution, color, and  properties ofj
      304.
  "   rate of its growth, 305.
      variety ol, in mammals, 311.
Hamster, a rodent animal.
Happiness the  object of all organs, 424.
Ilarde'rian gland, 283.
Harmo'nia, 66.
Haversian canals, 33.
Head of birds, 93.
Heart of man, 201.
  "   "  inaiiiiniils. 230.
  "   "  birds,  232.
  "   "  reptiles. 234.
  "   "  crocodile, . >0.
  "   "  fishes, 237
  "   '■  articulate.-, 239.
  '•   "  Crustacea, 241.
Heat producing organs, 256.
Hem'atin, 13.
Hepat'ic, pertaining to the  liver.
     "     artery, 212.
Uerbin'orous,  vegetable eaters.
Hexag'onal, with six sides.
Hippu'ric acid, 9.
Hiss of serpents,  272.
Hixtogenet'ic,  tissue making.
Hixtol'ogy, 14.
llDiioge'neoux,  of   the  sams character
  throughout.
Honey comb, 187.
Horn of rhinoceros, 311.
Hu'merus, 57,  91, 97, 100.
Humors of the eye, 374, 378.
Hy'drogen in the bodv, 6.
Hygrol'ogy, 14.
Hyoid bone, 55. 
436
INDEX   AND   GLOSSARY.
                     I.
 Ichorolfigy, definition of, 282
 Il'iac arteries, 212.
 Il'ium, 61.
 Imbibi'tion, 17.
 Iin'bricated, overlapping like shingles on
   a roof.
 Imme'diate principles, 7.
 Impurities exhaled from lungs, 255.
 Inci'sor teeth. 54.
 Indian club, 145
 Infuso'ria, microscopic animals.
 Ing.u'vies, 1S3.
 Inuomina'tum, 61.
 Iws-ula'tion—see anastomosis.
 Inspirations compared with pulsations, 255.
 Interartic'ular cartilage, 71.
 Intercos'tal muscles, 125.
 Intermaxillary bones, t-9.
 Interosseous, between the bones.
 Intes'tinal fluid, 16.
           glands, 163.
 Intes'tine, length of, 155, 1S9, 192.
 Inver'lebrate, without internal skeleton.
 Iris, 371.
 Iron in the body, 7.
 Irritability of muscular fiber, 134.
 Is'chium, 61.


                    J.
 Jeju'num,  161.
 Joints, design shown in them, 421.
   "    motions of,  6S.
 Jugal bone, 93.


                    K.
 Kidneys, 171.


                    L.
 Lab'yrinth, 391.
 Lach'rymal gland, 375.
     "      bones, 49.
 Lac'teals,  169, 180, 282.
 Lacu'na?, spaces.
    "     of bone, 33.
 Laeu'nar, tilled with lacunse*
 LameU'as,  thin layers or plate*.
 Laryn'geal, relating to the Larynx,
     "      pouches, 279.
 Lar'ynx, 243, 259.
        of birds, 279.
   "    "  reptiles, 2S0.
   "    its similarity to  a reed instru-
  ment, 264.
 Lead in the body, 7.
L 'Us of the eye, 874.
Life, characteristic of organic substances, 5.
 Li_'aments, 69.
            annular, show design, 423.
     "'      used as  braces, 74.
Lime, carbonate and phosphate of, 11.
Lin'gual nerves, 331, 351.
Liver, 165.
  "   of mammals, 189.
      "  fishes, 193.
Lob'ules of lung, 247.
Lower jaw, 50, 39.
Lumbar arteries, 212.                      I
 Lumbar plexus, 834.
 Lunglet, lobule of lung.
 Lungs, their liability to disease, 265.
    '■     "  action essential for health, 266,
    "   pure air essential to, 266.
    "   capacity of, as  affected by posture,
           267.
    "   capacity of may be increased, 267.
    "   of mammals, 270.
    "   " birds, 270.
    "  '" reptiles, 272.
 Lymph, 15.
 Lymphat'icE, 182, 284.
       "       their function, 2S7.
       "       material absorbed by, 2S7.
 Lymphat'ic hearts, 236.
     "       glands, 285.


                    M.
 Magne'sium in  the body, 7.
 Malar bones, 48.
 Malleolus, 64.
 Man not without hope, 429.
 Manganese' in tho body, 7.
 Man'dible, 50, 89.
 Mantle of Molluscs, 314.
 Many-plies, 187.
 Marmot,  a rodent or gnawing animal.
 Mass'eter muscle, 110.
 Mastication,  172.
 Me.'dia, or humors.
 Medull'a oblonga'ta, 322, 847.
 Meda's,e, radiate animals.
 Meibo'mian glands, 377.
 Membra'na tym'pani, 390.
 Membrane, simple, 17.
 Mesenteric artery, 212.
     "       glands, 109.
 Mes'entery, 168.
 Metamor'phosis, change.
 Metacar'pus, 60, 79, 91.
 Metatar'sus,  65.
            of birds,  97.
 Milk, 16.
 Mimo'sa,  plant  of the order leguminosw.
 Moisture,  its effect  upon lymphatics, 2S9.
 Molar teeth,  54.
 Mollusca,  So.
          skeleton of, 104.
 Motor, exciting motion.
   "   nerves, 336.
   "   oculi, 326, 351.
 Mouth, 155.
 Movements of radiata, 153.
 Mu'cus, 15.
 Muscles, number of in man, 111.
    "    suspensory, 152.
    "    of birds, feathers, 152.
    "    design shown in them, 421.
    "    looped, show design, 422.
    "    need use,  139.
    "      "  gradual rest, 140.
    "    require regular exercise. 140.
    "    time they may be employed, 154,
    "   forms of, 110.
    "    of the fore arm, 120.
           "   birds, 151.
           "   fishes, 152.
           "    articulates   and molluscs.
                  153.
Muscular development, 141. 
INDEX   AND  GLOSSARY.                 437
Muscular strength, examples of, 137,154.
    "     contraction, cause of, 135.
    "     movement, disadvantage of it, 136.
    "     contraction, its rapidity, 138.
    "          "      " duration, 138.
    "          "      " precision, 139.
Mus'culin, 12.
Myol'ogy, definition of, 107.
Myotility, 26, 134.
Mystery as  great in physiology as in relig-
  ion, 432.
Mystery in muscular movement, 432.
    "    in connection of mind and matter,
          432.

                    N.
Nails, 277.
Nasal bones, 48.
  "   duct, 375.
Nasmyth's membrane, 53.
Neck, its length dependent on, 87.
  "   how to be dressed, 269.
Nerve tubes and fibers, 317.
   "   vesicles or cells, 318.
Nerves over sensitive, 42S.
Nervous power shows design, 423.
    "     system, its hygiene, 352.
Neurol'ogy,  definition of, 310.
Nictitating membrane, 383.
Ni'trogen, 6.
Nitrog'enous,  containing nitrogen.
Normal, according to the standard.
Nose, 412.
Nostrils, 413.
     "     their use in the voice, 265.
Nu'clear, pertaining to a nucleus.
Nu'cleated, 13.
Nucleolus, 18.
Nu'cleus, 13.
                     0.
 Oil, 16.
  '■  glands, 299.
  ■'     "   use of, 307.
 O'lein, 11.
 Oif'ac'tory nerves, 325, 350.
 Oma'snm, 1^7.
 Omen'tum, 16S.
 Optic nerves, 326,  351.
 Orbicularis pal'pebr*, 114.
             oris, 115.
 Organ, definition of, 20.
 Organs adapted to circumstances, 426.
 Ornithoryn'chus, an  animal  of the
   mammalia.
 Os'cil'atory.  vibrating.
 Oss'icles, little bones.
 Os quadra'tum, 397.
 Os'tein, 12.
 Osteol'ogy, definition of. 31.
 Ot'oliths, bony particles of tho ear.
 Ovalbu'men,  12.
 Ox'ygen in the body, 6.

                     P.

 Pacin'ian coi puscles, 336.
 Pal'ate bones, 49.
 Palmar arch,  209.
 Pan'creas, 166.
 Pancreat'ic fluid, 16.
 Papil'lse, 295, 400, 408.
 P*r'asite of skin, 299.
Pari'etal bone, 44.
Patell'a, 63.
Paunch, 187.
Pecten  marsu'pium, 884.
Pedun'cle, a stalk or stem.
Pedunculated, having a stalk or peduncle.
Pelvis, bones of, 61.
Ven'niform, feather-shaped.
Pep'sin, 15,  160.
Pericar'dium, 204
Perilymph, 391.
Perios'teum, 34.
Peristal'tic, moving like a worm.
Peritone'um, 16S.
Perspira'tion, 8ul.
Peyer's patches, 163.
Phalanges, 60, 65, 79, 91, 97.
Pliaryn'geal, belonging to the pharynx.
Pha'rynx, 156.
Phos'phorus in the body, 7.
Phvsiology, definition of, 6.
Pia* ma'ter, 324.
Pig'ment cells, 296.
Pigmen'tary spots, 385.
Pignien'tum ni'grum, 372.
Pinna, 3S9.
Pitu'itary  membrane, the  lining mem-
  brane of the nose.
Placoid'ians, 314.
Plan, unity of, in animal system, 424.
Plasma, watery portion of the blood.
Plas'tron, 99.
Pleasure superadded to functions when not
  necessary, 425.
Pleura, 248.
Pleurisy, 248.
Plexus, 332.
Pneumogas'tric nerves, 830,  851.
Pneumonol'ogy, definition of,  244.
Poison introduced by lymphatics, 2S3.
Polyhe'dral, with many ends.
Polyps, radiate animals.
 Poplit'eal artery,  213.
 Pores of bones, 34.
 Portal  system, 218, 236.
 Potass'ium in the body, 7.
 Power reserved for exigencies, 426.
    "   vicarious in organs, 426.
    "   recuperative in the system, 427.
 Prehen'sile, adapted for seizing.
 Prehen'sion, the act of grasping.
 Primary tissue, 14, 22.
 Principles, immediate, grouped, 8, 9.
 Prismoid, like a prism.
 Pris'tine,  primary.
 Process, an elevation on a bone.
 Processes of bones, 35.
 Pro'tein, 13.
 Psoas muscle, 126.
 Pty'alin, 172.
 Pu'bis, 61.
 Pulsations of heart, 227.
 Pylor'ic appendages, 194.
 Pylo'rus,  tue lower orifice  of the stomach.

                     Q.
  Quadran'gular, with 4 angles.
  Quadrilat'eral,    "  "  sides.

                    B.
  Ea'dial artery, 208.
  Eadia'ta, S5.
class 
438                  :ndkx  and
Radiata, skeleton of, 106.
Radicals, organic, 8.
Ra'dius, 59.
Ram'ify, to give on" branches.
Rectum, 162.
Red or Rennet, 133.
Reflex actions in articulates, 363.
Religious applications of anatomy, 420.
Respira'tion, process of, 2.")2.
Respi'ratorv organs  of mammals, 270.
      "        "    '• birds, 270.
      "        "    " reptiles, '272.
                    " fishes. 275.
      "        "    " articulates, 276.
      "        "    " molluscs. 27s.
      "        "    " radiate--, 279.
Retic'ulurh, 186.
Ret'ina, 372.
Retractile, capable of being drawn back.
Ribs, 55, 96.
Rickets, cause of, S2.
Ro'dent, gnawing.
Rota'tion, 6S.
Rii'minnnts, animals that chew the  cu
  like the cow.
                   S.
Sac/ciform, like a sa<-.
Sa'cral plexus. 334.
Sa'crum, 41.
Sali'va, 16, 172.
Sal'ivary glands, 155.
Salt in the human body, 11.
Sapona'c.eous, soapy.
Sarcolem'ma, 103.
Scales of serpents, 313.
       " fishes, 814.
Scap'ula, 57.
Scepter, Indian, 145.
Schindylesis,  06.
Science, its highest use, 420.
Seba'eeous glands, 299.
Sclerof ica, 369.
Scle'rous, hard like bone.
Seeiv'tion, vicarious. 292.
           after death, 291.
    "      function of,  291.
    "       effect of emotions upon, 291.
Sfi/'menfo, divisions.
Seiuicir'cuhir  canals, 391.
Sensa'tions, effect of habit upon, 868, 402.
Senses often a source of misery, 418.
   "   dependent on mind, 367.
   "   effect of excessive use of, 367.
   "   development in lower animals, 367.
Sensual happiness not perfect, 419.
Seralbu'men,  12
Serra'ti muscles, 125.
Se'nun,  15.
Ses'anioid bones, 65, 97.
Sighted, long  and short, 3S1.
Sil'icon in tlie body, 7.
Si'nuses, 217.
Skeleton, design showed in, 421.
    "     human, weight of, 32.
Bkin,  295.
   "   uses of, 305.
   "   its hygien'ic value, 303.
   "   attention necessary for, 3C9, 310.
   "   of mammals, 310.
   "   "  birds, 312.
GLOSSASJ1
Tac'tile, susceptible of touch.
Tailor's muscle, 129.
Tape'tuui, 3S3.
Tarso-metatar'sus, 97.
Tarsus, 64, SI.
Taste, nerves of, 407.
   "   effect of education upon, 408.
   "   its connection with smell, 409.
   "   a guide for the appetite, 418.
Tears, 16, 330.
Teeth, human, 51.
   "   esophageal, 192.
   "   of reptiles, 191.
   "   of fishes,.102.
   "   development of, 53.
   "   names of, 54, 90.
   "   fracture of, 54.
   Skin  of amphib'ia, 313.
  |   "   " ra'diates, 815.
   Sleep, 342, 347.
   Smell under control of tho will, 414.
     "   sense of, in animals, 414, 416.
   So'dium in the bodv, 7.
   Snlar plexus, 340.
   Solitary glands, 163.
   Sound, organs essential for, 264.
   Sounds of heart, 227.
      "    " insects, 280.
      "    "  mollusca, 231.
   Special sense, nerves of, 363.
   Sphe'noid bone, 45.
   Sphinc'ter, 111.
   Spinal cord, 322, 332, 343.
     "   column, 42, 73, S5.
     "   nerves, 332,352, 353.
     "   accessory nerve, 830, 851.
   Spi'racles of insects, 276.
   Splanchnology, 155.
   Spleen, 293.
   Sple'nic artery, 212.
d  Stell'ate,  star-shaped.
   Stem'mata, 337.
   Sternum, 55, 96, 101.
   Sterno-cleido mastoid muscle, 116.
   Stim'ulants, their value and injury, 1S5.
   Stomach,  153.
       "    of ruminants, 187.
       "    " birds, 190.
   Styloid bones, 89.
   Subcla'vian artery, 206.
   Sugar in  the body, 11.
   S'liphur •'    "    7.
   Superior  Mnx'illary. 50.
   Snppura'tion, foiming of pus.
   Suspen'sory muscle, 152.
   Sutu'ra, 66.
   Su'tuies,  46.
   Sweat,  17.
      "    glands, 299.
   Sympathetic system, 337, 348, 853.
                ganglia, 339.
   Sympathy between heart and lungs, 245.
   Sym'physes, 07.
   Synarthrosis, 06.
   Syn'chronoux, at the same time.
   Syndesmol'ogy, definition of, 66.
   Syno'vial membrane, 73.
   Systems of organization mutually depe:
      ent, 424.
   Sys'tole,  226.

                        T, 
INDEX  AND
Teeth, care needed for, 82.
   "   generally decay early in life, 83.
Teg'ument of articulata, 314.
Tegument'ary, relating to the skin.
Tegument'ary muscle, 150.
Temperature  of human body, 257.
Tem'poral bone, 43T
     "     muscle, 116.
Tendons of fingers and toes, 120.
    "    ossification of, in birds, 151.
Tens t vag'ime fem'oris, 129.
Tento'rium, 358.
Thal'ami op'tici, 322.
Tlioracic,  pertaining to the chest.
Thorac'ic duct, 170.
    "     aorta, 211.
Thy'roid cartilage, 260.
Tib'ia, 63.
Tib'ial artery, 213.
Time during  which .muscles can be  used,
  154.
Tissue, simple fibrous, 22.
   "    white fibrous, 22.
   "    yellow  "    22.
   "    areolar, 23.
   "    fihro-cellular, 23.
   "    cellular, 24.
   "    sclerous, 24.
   "    tubular, 25.
   "    muscular, 26.
   "    nervous, 28.
Tobacco, its effect on the brain, 355.
Tongue, human, 406,
    "    of reptiles, 191.
    "    use o£ in speech, 265.
Tonic'ity, muscular, 134.
Tonsils, 155.
Tortoise shell, 99.
Touch, instruments of, 400.
   "    of lower animals, 403, 405.
Tra'chea, 248.
    "    of mammals. 270.
    "     " insects, 276.
Transverse, crosswise.
Transudations, 15.
Triangle for exercise, 145.
Triceps muscle, 119.
Trifacial nerves, 326, 351.
Trill of birds,  279.
Triquet'ra ossa, 47.
Trochan'ter process  upon  the upper part
  of the femur.
Trochlear nerves, 326.
Tuberc'ula quadrigem'inn, 322.
Tur'binal bone, 49.
Tym'panic bones, 88.
Tym'panum, 390.
GLOSSARY.                 439
                   U.
Ulceration, ulcer-forming.
Ulna, 5S.
Ulnar artery, 208.
Unicel'lular animals, 199.
Uniformity of animal heat, 258.
Unity, Divine, proof's of from anatomy, 430
  "     "     proved  by the conspiration
  of all the parts, 430.
Unity proved by mutual relation,  430.
Urine, 16.
                   V.

 halves of the heart, 203.
 Veins, 217.
  "    valves of, their discoverer, 219.
 Ventral trunk, 241.
 Ven'trieles, 202.
            of brain, 324.
 Ventn'ri, principle of, 1S1.
 Ver'tebra, cervical, 40, 85, 93.
     "     dorsal, 41, 85, 93.
     "     lumbar, 41, 85.
     "     sacral, 85.
           caudal, 85, 93.
 Ver'tebral artery, 209.
 Vertebra'ta, 85.
 Vessels protected, 423.
 Ves'tibule, 391
 Vibra'tile, susceptible of vibration.
 Villi, hair-like appendages.
 Viscera, contents of an animal cavity.
 Viscid, thick like syrup.
 Vision, limits of, 382.
 Vitaliza'tion, the act of giving lifo.
 Vitreous humor, 375.
 Vocal cord, 262.
 Voice, organs of, 259.
   "   its strength dependent on, 269.
 Voluntary motions,  on what dependent,
 ^340.
 Vo'iner, 51.

                  w.
 Waste the cause of muscular contraction,
  135.
Water in the body, 10.
  "   amount consumed by an adult, 11.
  "       "    discharged by the skin, 302
Wax, 16.
Wonder nets, 231, 234.
Wounds of arteries, 229.
World fallen, proof of, from anatomy, 428L 
INDEX    OF    CUTS.
FIG.                           PAGE
  1 Blood Crystals................   9
  2    "     "    ................  10
  3    "     "    ................  13
  4 Milk...........................  16
  5 Simple Fiber...................  17
  6 Cells..........................  18
  7   "   ...........................  18
  8 Caudate Cells.................  19
  9 Stellate  "  .................  19
 10 Development of Cells........  20
 11      "       "    "   ........  20
 12      "       "    "   ........  21
 13 White Fibrous Tissue.........  22
 14 Yellow   "      "    ........  22
 15 Areolar Tissue.................  23
 16 Cells  of Areolar Tissue.......  23
 17 Adipose Tissue..........".......  24
 18 Cartilaginous Tissue..........  24
 19 Osseous         "   ..........  25
 20 Lacunae op Bone..............  25
 21 Lymphatic Vessel.............  20
 22 Muscular Tissue..............  26
 23 Diagram op Muscular Fibril..  26
 24 Muscular Tissue...............  27
 25     "       "  ...............  27
 26     "       "  ...............  27
 27 Tubular Nerve Tissue........  28
 23 Vesicular  "     "   ........  28
 29     "      "     "   ........  29
 30 Fibula after Immersion in Mu-
     riatic Acid..................  32
 31 Canaliculi of Bone...........  33
 32 Lacuna    w   "  ..........  34
 83 Ultimate Granules of Bone..  34
 84 Periosteum.....................  35
 85 Development of Cartilage...  37
 36 Knee  Joint....................  38
 87 Lateral View of Spinal Col. .  38
 38 View of Human Skeleton.....  39
 39 Atlas..........................  40
 40 Axis............................  40
 41 A  Dorsal Vertebra...........  41
 42 Sacrum........................  41
fig.
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 53
 59
 60
 61
 02
 63
 64
 65
 G6
 07
                           PA03
Coccyx........................   41
A Dissected Skull.... ,.......   43
Frontal Bonf  ................   43
Temporal  "  .  ...............   44
Parietal   "  ...............   41
Occipital  "  ...............   45
Sphenoid   "  .................   45
Ethmoid   "  .................   46
Vault of the Cranium........   46
Front View op  the Skull....   47
Nasal Bones......... ........   48
Malar Bone...................   43
Lachrymal Bone...............   49
Palate     "  ...............   49
Turbinal   "  ...............   49
Maxillary  "  ...............   50
Mandible......................   50
Vomer..........................   51
Section of Human  Incisor....   52
   "    "    "    Bicuspid....   52
   "    "    "     Incisor__   52
   "    "    "    Molar.....   52
Enamel of Tooth..............   53
Permanent Teeth.............   54
Hyoid Bone....................   55
Sternum........................   55
Upper Rib......................   55
Ribs............................   56
Bones of the Chest...........   56
Clavicle.......................   57
Scapula........................   53
Humerus.......................   58
Fore-Arm......................'.   59
Carpal Bones..................   60
Bones of the Hand............   60
Pelvis.........................   61
Innominatum...................   62
Femur.........................   62
Patella........................   63
Tibia and  Firula  ............   64
Bones of the Foot............   64
Development of Cartilage....   60
Ligaments of the Pelvis......   70 
INDEX   OF   CUTS,
441
FIG.
 86
 87
 90

 91
 92
 93
 94
 95
 96
 97
 93
 99
100
101

102
103

104
105
106
107
108
109
110
111
112
113

114
115
116

117

113

119
120
121
122
123
124
125
126
127
123
129
130
131
132
                           PAGE
Ligaments of the Shoulder—  70
    "     "   '•  Hip.........  71
    "     "   "  Knee........  71
    "     "   "  Lower Jaw.  72
    "     "   "  Vertebra
  and Ribs.....................  72
Ligaments of the Elbow......  72
    "     "   "  Ankle......  73
    "     "   "  Foot.......  73
    "     "   "  Ankle......  74
Skeleton op  Camel............  86
    "    "   Bat...............  86
    "    "  Cameleopard__  87
    "    "   Mole.............  88
Head of Horse................  89
Teeth of Lion.................  90
Teeth of an Herbivorous Ani-
  mal............................  91
Teeth of an Insectivor. Animal 91
Anterior Extremities  of Dif-
  ferent Animals..............  92
Hind Foot op Horse...........  92
Foot of Stag..................  92
Skeleton of  Swan............  94
    "      il   Gotland..........  95
Head of Eagle................  95
Bones of Sternum _ Shoulder.  96
Skeleton of  Tortoise.........  99
    "      "   Frog.............  100
    "      "  Perch............  101
Section of the Scale op Lepi-
  dosteus.......................  101
Head of the Pike..............  102
   «  "  "   Shark............  102
Microscopic  Structure  op
  Tooth of Eagle Ray.........  103
Microscopic Structure  of Spine
  of Hedgehog.................  104
Microscopic View of Shell of
  Pinna.........................105
Microsc. View of Shell of Mya 105
Development of Muscul. Fiber 107
Fragments    "    "         108
Muscular Fibril............... 108
Section of Fibril.............. 109
Myolemma...................... 109
Cells of Muscular Fiber.....  109
Radiate Muscle................ 110
Fusiform  "   ................110
Doubly Penniform Muscle--111
Muscular System.............. 112
                ..............  113
Transverse Section op  Neck. .. 114
Muscles op Face and Neck--115
    »     "   "   "    "   Side
  View.........................  H7
fig.                           pag_
134 Muscles of Back............... 118
135   "     "  Arm................ 119
136   "     '•  Hand  _ Fore-Arm. 120
137   "     "  Palm of Hand.....121
13S   "     "  Fore-Arm  (deep
     Layer).......................121
139 Muscles of Back............... 123
140 Diaphragm..................... 125
141 Muscles of Trunk (Side View). 126
142   "     "  Abdomen........... 1-7
143   "     "  Thigh.............123
144   "     "    "  (Back View).. 130
145   "     "  Front of Leg...... 130
146   "     "  Back of Leg....... 131
147   "     "  Foot................ 132
148   "     "  Back of Fore-Arm. 133
149   "     "  Front of Leg..... 133
150 Diagram of Fibrill_:.........134
151   "     "  Disadvantage  of
     Muscular Action............ 136
152 Muscular Fiber Contracting.. 137
153 Back Board.................... 144
154  "     "  in Use............. 145
155 Indian Club................... 145
156 Uses of Indian Club........... 146
157 Triangle....................... 145
153 Use of Triangle................ 145
159 Apparatus of a Gymnasium... . 147
160     "      "     "       ....  14S
101     "      "     "       .... 149
162 Fibrils of Pig.................. 151
163   "    " Meat Fly........... 153
164 Insect Fasciculi................  153
165 Salivary Glands...............156
166 Follicles from Tonsils........ 156
167 Section of Mouth and Pharynx 157
168 Esophageal Glands............ 158
169 Human Stomach............... 158
170 Coats of   "    ............... 159
171 Diagr. of Stomach _ Intestines 160
172 Gastric Glands................ 160
173 C_:cum and Appendix..........161
174 Human Digestive Apparatus.. 163
175 Peyer's Patches................ 164
176 Brunner's Gland..............164
177 Villi of Jejunum. ............ 164
178 Human Liver..................  106
179 Lobule of Liver...............  106
180 GallBladder...................  167
181 Pancreas and Spleen..........  167
182 Peritoneum.................... 168
183 Chyliferous  Vessels...........  169
184 Thoracic Duct.................. 170
185 Kidney......................... 171
186 Diaoram of  Urinary  Appara-
     tus............. ............. 171 
442                   INDEX  OF  CUTS.
fig.                           page
137 Diagram of Position orTnoRA-
     cic Duct and Jugular Vein.. 181
183 Principle of Venturi......... 132
189 Digestive Apparatus of Ape. .. 186
190 Stomach of Sheep.............. 137
191 Interior of  "  ............... 1S7
192 Stomach of Ox................. 133
193 Head of Woodpecker.......... 189
194 Digestive Apparatus of Fowl 190
195 Head of Rattlesnake.......... 191
U)o Anatomy of Snake............. 193
1J7 Digestive Apparatus of Beetle 194
193 Viscera of Aplysia (Mollusc). 195
199     "    "  Star Fish.......... 195
200 Fresh Water Polyp........... 197
201 Digestive  Apparatus  of  uni-
      oellular Animals............ 198
202 Human Heart.................. 201
203 Fibers of the Heart........... 202
204 Heart and Lungs..............202
205 Diagram of Heart.............203
206 Valves of Heart.............. 204
207    "    "  Aorta............... 204
208 Arterial System................ 205
209 Middle Coat of Arteries......206
210 Heart and Arteries in Situ.... 207
211  Arteries of Neck _ Shoulder . 208
212     "    "  Arm and Hand__209
213 Circle of Willis............... 210
214 Abdominal Aorta..............211
215 Femoral Artery............... 212
216 Arteries of Backside of Leg... 213
217 Capillaries........--........ 214
218 Veins of Face and Neck....... 215
219    "  "  Trunk and Neck..... 216
220 Sinuses of Brain............... 217
221 Valves of Veins............... 218
222 Veins of Arm.................. 219
223    "  " Leg...................220
224 Blood Crystals................ 221
225 Red Blood Corpuscles......... 221
226 Diagram of Heart's Contract.. 227
227 Circulation in Mammals....... 230
223 Diagram of Varieties of Aorta
      in Mammals.................. 231
229 Blood Corpuscles  of Ox....... 231
230 Blood Crystals of Guinea Pig. 232
231 Arteries of the Grebe.........233
232 Pigeon Blood Corpuscles...... 234
233 Diagr. of Circulat. of Reptiles 234
234 Blood Corpuscles  of Frog..... 234
235 Circulat. Apparatus of Lizard 235
236 Heart of Crocodile............ 236
237    "   " Turtle............... 236
23^ Diagram of Circulat. of Fishes 237
239 Circul_tixg Vessels in the Fish 238
fig.                            pagb
24J Blood Corp uscles of Eel...... 239
251 Plan of Circulation in Fishes. 239
242 Circulatory Appapatus  of the
     Lobster...................... 240
243 Circulat. Apparatus of Insects 240
244 Blood Corpuscles ok Crab..... 241
245 Anatomy of the Snail.......... 242
246 Heart and Lungs.............. 244
247 Bronchi and Vessels in Srru... 245
248 Thoracic Viscera in Situ...... 246
219 Lunglet........................ 247
250 Diagramatio Section of Thora-
     cic Viscera................... 249
251 Capillaries of Human Lung... 250
252 Magnified  Section of Lung__ 250
253 Termination of Bronchus..... 251
254 Bronchial Tube laid open..... 251
255 Lateral View of Larynx...... 259
256 Thyroid Cartilage............ 260
257 Arytenoid    "   ............ 260
258 Cricoid      "   ............ 261
259 Epiglottis..................... 261
260 Larynx......................... 261
261     "   ....................... 262
2G2     "   ........................ 202
263 Larynx and Epiglottis........ 203
264 Lungs of a Bird................ 271
265 Lungs, etc., of a Pigeon....... 271
266 Lunglet of a Fowl ........... 272
267 Lungs of a Frog............... 272
26S   "    " Serpents............. 273
269 Dissected Lung of Turtle..... 274
270 Gills of Eel................... 274
271 Air Bladder of Fish........... 275
272 Trachea of Water Scorpion... 276
273 Spiracle of Fly................ 277
274 Lymphatics..................... 282
275 Lymphatic System............. 2S3
276 Lymphatics of Axilla.......... 284
277 Thoracic and Lymphatic Ducts 285
278 Lymphatics of Abdomen........ 286
279      "      " Tuicn........... 237
280 Diagram of a Gland........... 290
281 Cu yliferous Vessels........... 290
282 The Spleen..................... 293
283 Intimate Structure of Splee.-. 293
234     "        "     "     "   293
235     "        "     "     "   294
2S6 Papilla of Hand..............295
237 Epidermis of Negro............296
288 Pigment Cells.................. 296
2S9 Section of Thumb..............297
290 Cerumen Gland................ 299
291 Parasites of the Fat Glands.. 300
292 Skin op Palm of Hand......... 301
293 Perspiratory Gland........... 30J 
INDEX  OF  CUTS.                   443
fig.                            page
294 Sections of Human Hair....... 302
295 Skin of Scalp..................303
296 Root of Hair.................. 304
297 Hair of Human Beard.......... 305
298  "   "  Sable.................311
299  "   "  Musk Deer............311
300  "   "  Squirrel.............. 312
301  "   "  Pecari................312
302 Tubular Nerve Cells.......... 317
308 Vesicular  "    "    .......... 318
304 Section op Brain, etc...........319
805   "     "    "   .............320
306 Cerebellum..................... 320
307 Base op Brain..................321
308 Cerebro-Spinal Axis .  ......... 322
309 Sinuses of Brain...............323
310 Olfactory Nerves.............. 325
311 Optic Nkrves................... 320
312 Third,  Fourth, and Sixth Cra-
      nial  Nerves.................. 327
313 Trifacial Nerve............... 327
314      "       "   ............... 323
315 Auditory    "   ............... 32S
316 Tenth  Pair of Nerves........ 329
317 Nerves of Tonguf, etc.......... 330
318 Portion of Spinal Cord........ 331
319 Diagram showing Decussation 332
820 Nervous System................  333
321 Brachial Plexus...............  334
322 Nerves of Fore-Arm........... 334
823 Ischiatic Plexus...............335
324 Crural Nerve, etc............. 335
325 Nerves of the Foot............ 336
326 Pacinian Corpuscles........... 336
327 Sympathetic Nerve............ 338
 328 Union of Spinal and Sympa-
      thetic Nerve................. 339
 329 Brain of Squirrel............. 357
 330   "   " Rabbit............... 357
 331   "   " Buzzard.............359
 832   "   " Turtle............... 360
 333   "   " Fishes................ 361
S34 Electrical  Appae. of Torpedo. 362
fig.                           page
335 Nervous System of Articulates 362
336     "     •'   "  Beetle..... 363
337     "     "   "  Argonauta 364
338 Nervous System of Star Fish.. 365
839 Globe op the Eye............... 370
340 Plan of the Structure of the
     Eye........................... 371
341 Choroid Coat................... 371
342 The Iris........................ 372
343 Thf, Eye Dissected.............. 372
344 Microscopic Section of the Re-
     tina.......................... 373
345 Crystalline Lens, Front View 374
346      "       "  SiDEyiEW.. 374
347 Lens at Different Ages....  ... 374
34S Eyelids & Lachrymal Glands.. 375
349 Lachrymal Canals............ 876
350 View of  Eye and Append-
     ages.......................... 376
351 Meibomian Glands............. 377
352 A Single Meibomian Gland.... 377
353 Muscles of the Eye............ 377
354 Head and Eye of the Bee...... 386
355 Section of one Facet.......... 386
356 Eye of Trilobite............... 387
357 The Left Ear..................389
358 External and Internal Ear .. 3^9
359 Cavity of the Tympanum....... 390
360 Membrana Tympani............391
361 Ossicula Auditus.............. 391
362 Labyrinth and Tympanum .... 392
363 Cochlea without the Nerve... 392
364 Nerve without the Cochlea... 393
365 Nerves of Extremity of Thumb 400
366 Papilla of tub Palm.......... 400
867 Foot of a Fly.......:.......... 405
363 Human Tongue................. 406
369 Papilla of Tongue............ 407
370 Head op Woodpecker.......... 410
371 Tongue of Fly.................411
372 Cartilages of Nose............412
373 Section op Nostrils..........., 418 
X..
"■***  /'
J,-  7
sT-^l/
wt- -x-e

/~U£---/*...
>
x
1 '"/Yb
{?/   V
9/7 * ;/7
/>>'
fcS*-*-*.*^  -o
 
 
Sf_$
1*1