AUTHOR’S EDIT'IOISr. 
DEPARTMENT OF THE INTERIOR. 
UNITED STATES GEOLOGICAL AND GEOGRAPHICAL SURVEY. 
F. V. HAYDEN, U. S. Geologist-in-Charge. 
PRECURSORY NOTES 
ON 
AMERICAN INSECTIVOROUS MAMMALS, 
WITH 
DESCRIPTIONS OF NEW SPECIES. 
BY 
ELLIOTT COUES, 
CAPTAIN AND ASSISTANT SURGEON UNITED STATES ARMY, 
SECRETARY AND NATURAUIST OF THE SURVEY. 
EXTRACTED FROM THE BULLETIN OF THE SURVEY, Vol. HI, No. 3. 
Washington, May 15, 1877 ART. XXV.—PRECURSORY NOTES ON AMERICAN INSECTIVOROUS 
MAMMALS, WITH DESCRIPTIONS OF NEW SPECIES. 
By Elliott Coues, 
Captain and Assistant Surgeon TJ. S. A., Secretary and Naturalist of the Survey. 
Although the material before me for a monographic revision of the 
American Insectivora is much greater than has been at the command of 
any previous investigator, I am not yet prepared to announce the final 
results of my study, there being several points still awaiting determina- 
tion. Meanwhile, however, I think it advisable to publish without 
delay descriptions of such species as appear to be unquestionably new 
and valid, together with a number of other points which I consider 
established. These relate largely to the recognition of the excellent 
subgeneric distinctions w7hich subsist among the Soricida. These 
notes may be considered preliminary to a monograph of the American 
Insectivora, now in preparation, the publication of which, however, may 
be long delayed. 
Yery little has been done with these Mammals since 1857, when Pro- 
fessor Baird* so greatly increased our knowledge of the subject. Though 
the species admitted by him at that date, upon consideration of the 
very limited material then at his command, require to be largely re- 
duced, all the generic and subgeneric distinctions indicated by him are 
confirmed. The species additional to those given by him rest without 
exception upon specimens not at that time available. In 1861, the 
same naturalist reviewed the subject, making many new and important 
determinations, which, however, have never been published. Most of 
the new subgenera and species to be described in this paper are derived 
from his MSS., which he very generously placed at my disposal, when 
all the material contained in the National Museum, Smithsonian Insti- 
tution, was given into my hands for elaboration. 
The principal contributions to the knowledge of the subject since 1857 
have been made by J. A. Allen and T. Gill. The former reviewed the 
genus Blarina,t coming to the conclusion, not supported by larger ex- 
perience, that all the species of this genus were reducible to one, con- 
sidering that Baird’s section of Blarina with 30 teeth was based upon 
t Catalogue of the Mammals of Massachusetts: with a Critical Revision of the Spe- 
cies. < Bull. Mus. Comp. Zool., Cambridge, i, No. 8, pp. 143-252. 1863. (Blarina, 
treated at pp. 213-221.) 
* Mammals of North America, 1857, pp. 4-77. 632 
BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
the immature dentition, and suggesting that such was probably also the 
case with the corresponding sectiou of Sorex with 30 teeth. But these 
sections are perfectly valid, and to them I add a third, in Sorex, of 28 
teeth. Iu 1875, Dr. Gill* elaborately reviewed the Insectivorous Mam- 
mals atlarge, and proposed, mainly upon the basis of St. George Mivart’s t 
investigations, verified by original examination of much material, a class- 
ification of the order believed to be the best yet presented. This valuable 
article is especially full in its treatment of the two North American fam- 
ilies, Talpidce and Soricidcv, and gives an extensive bibliography, but 
scarcely touches upon the characters of the genera and species. 
Among other points may be mentioned the determination, by Pro- 
fessor Verrill,! of the Sorexpalustris of Richardson as a valid species of 
Neosorex; and the identification by Hr. Peters § of the Scalops latvnanus 
of Bachman with S. townsenii of same author. 
The most noteworthy laborer in this field before 1857 was Dr. Bach- 
man, whose results, however, required much remodeling. The determi- 
nation of his Sorex fimbripes was made by Professor Baird iu I8G1 from 
examination of the type, but is now first published in this paper. 
§1.—THE AMERICAN GENERA OF TALPID'M. 
America furnishes four good genera of Moles, namely, Scaops, S a 
panus, Condylura, aud TJrotrichus. The last-named belongs to a special 
subfamily, Myogalince, primarily distinguished from the Talpince by the 
characters of the scapular arch and fore limb. It is related to the Des- 
mans of the Old World, and is the only known insectivorous genus com- 
mon to both hemispheres, furnishing one of the many evidences of a 
relation between the faunas of Western North America aud Asia closer 
than that subsisting between Eastern North America and Europe* 
Scalops and Condylura, remarkable genera peculiar to America, have 
been recognized almost from the first; but the very strong claims of 
Scapanus to full generic rank have not been generally conceded. The 
genus differs so widely iu dentition from Scalops that it would accord 
more closely with modern valuation of generic characters to give it full 
rank and subdivide it into two subgenera for the accommodation of it 
two remarkably distinct species, than to force it under Scalops, from 
whi h it differs more than some of the Old World genera do from each 
* Synopsis of Insectivorous Mamma . < Bull. U. S. Geol. and Geogr. Surv., 2d ser., 
No. 2, pp. 91-120. May 14, 1875. 
t Notes on the Osteology'of the Insectivora. < Journ. Anat. and Phys., i, 1867, pp. 
281-312; ii, pp. 117-154. (French translation : Notes sur l’Ostdologie des Insectivores... 
< Ann. Sc. Nat., 5es6r., zool. et paldont., viii, 1867, pp. 221-284 ; ix, 1868, pp. 311-372.) 
On Hemicentetes, a new genus of Insectivora, with some additional remarks on the 
osteology of that order. < Proc. Zool. Soc. Lond., 1871, pp. 58-79, pl.v. 
1 Proc. Bost. Soc. Nat. Hist., ix, 1862, pp. 164-172, 225,226. The same determina- 
tion had been made by Baird in 1861 (MS. ined.). 
§ Monatsb. Konig. Preuss. Akad. Wissensch. Berlin, 1863, p. 656. COUES ON INSECTIVOROUS MAMMALS. 
other. In fact, it is scarcely less distinct from Scalops than from Talpa 
itself. 
In this connection, I may notice the repeated ascription of 11 Talpa ” 
to this country. The allegations to this effect have apparently arisen 
in two ways: from pure assumption and from mistaking of Scapanus 
breioeri for Talpa europcea. The superficial resemblance of these two 
species is really curious; so close is it that casual examination might 
easily fail to detect any difference in external characters. Audubon and 
Bachman allude to specimens observed in the Museum of the Zoological 
Society of London marked 11 Talpa europea from America ”. 
Recent researches render it most probable that the current dental 
formuhe of our genera require to be reconsidered—not as to the total sum 
of the teeth nor as to their physical characters, but as to their morpho- 
logical relations and their homologies. This is a subject, however, upon 
which I do not propose now to enter.* 
§ 2.—THE AMERICAN SPECIES OF TALPIDJE. 
For aught that we now know to the contrary, the determination of 
our species offers no difficulty, if we regard the Scalops argentatus Aud. 
& Bach, as at most no more than a geographical race of S. aquaticus. 
The authors themselves were only “ induced after some hesitation and 
doubt'to designate it as a new species” (Quad. N. A., iii, p. 253), and 
Baird questions “ whether the two can with entire propriety be sepa- 
rated” (Mamm. N. A., p. G3). It is certain that none of the ascribed 
characters are infallibly diagnostic. 
No further material bearing upon the relationships of Urotrichus gibbsi 
and TJ. talpoidcs having come to hand, the case remains as Baird left it. 
My present determination of our Talpidcc gives the following results:— 
Family TALPIDJE. 
Subfamily Tallinn 
Genus Scalops, u Cuv. 1800 ”. 
1. SCALOPS. AQUATICUS (L.)» 
Talpa flavescens, Erxl.—TT. fusca, purpurasoens, Shaw. 
Scalops canadensis, Dosm. (uec Rich.).—S. pennsylvanica, Harl. 
1 a. Scalops aquaticus argentatus (Autl. & Bach.). 
S. argentatus, And. & Bach. 
* Cf. Spence Bate “ Oa the dentition of the common mole (Talpa europsea)”, Ann. 
Mag. Nat. Hist., xix, 1867, pp. 377-381, plate; and Trans. Odontogr. S >c. Lond., v, 1867, 
pp. 261-294, pi. vi; also Mosely and Ray-Lankester “ On . . . the dentition of the 
mole ” , Journ. Nat. and Phys., iii (2d ser. ii), 1869, pp. 73-80, pi. ii, figs. 5, 6. BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
Genus Scan anus, Pomel, 1848. 
2. SCAPANUS TOWNSENDI (Bacll.). 
Scalops townsendii, S. latimanus, Bach.—S. canadensis, Rich, (nec auct.).—SS. 
metallescens, ceneus, Cass. *—S. tceniata, Le C.t—S. californica, Ayres.i 
3. SCAPANUS BREWERI (Bacll.). 
(“ Talpa europeea ex America”, Aliq.) 
v Genus Condylura, 111., 1811. 
4. Condylura cristata (L.). 
Sorex cristatus, L.—Talpa longicaudata, Erxl.—T. radiata, Shaw.—T. longicauda, 
Bodd.—C. macroura, Hart.—C. prasinata, Harris.^ 
Genus Urotrichus, Tenim., 1842. 
5. Urotrichus gibbsi Bd. 
(f=U. talpoides, Temm.) 
§ 3.—GENERAL REMARKS ON THE SOBICIDJS. 
Study of our Shrews will not give results with requisite precision, no 
matter how great the accessious of material, until we know more than 
we have yet learned of the limits of geographical and individual varia- 
tion to which the same species may be subject. I am not aware that a 
single one of our species has yet become fully known in these respects, 
and we are still obliged to rely somewhat upon analogies which the 
cases of better known European species may afford. In treating of 
Blarina talpoides from this point of view, Mr. J. A. Allen [loc. supra tit.) 
certainly overreached the mark; yet enough has been ascertained to 
render it certain that he was right in insisting that a much wider range 
of geographical and individual variation exists than is admitted, infer- 
* 1853.—Cassin (J.).—[Exhibition of a new mole, Scalops metallescens (descr. nulla).] 
Proc. Acad. Nat. Sci. Pliila., vi, Feb., 1853, p. 242. 
[Described, ibid., p. 299, as S. ceneus.'] 
1853.—Cassin (J.).—Description of a new mole of the genus Scalops, from Oregon ; 
a specimen of which is in the collection of the Exploring Expedition made by the 
U. S. ships Vincennes and Peacock, under the command of Captain Charles Wilkes, 
of the United States Navy. <( Proc. Acad. Nat. Sci. Pkila., vi, 1853, p. 299. 
[S. ceneus—named, not described, ibid., p. 242.] 
Mr. Cassin, whether intentionally or inadvertently, applied these two names to the 
same specimen. 
tl853.—Le Conte (J.).—[Remarks on the species of Scalops in the Collection of the 
Philadelphia Academy.] <[ Proc. Acad. Nat. Sci. Pkila., vi, June, 1853, pp. 326, 327 
(name on p. 327). 
11855.—Ayres (W. O.).—“ On Scalops californicus.” <Proc. Cala. Acad. Sci. i, May, 
1855, p. 54. 
§ 1825.—Harris (T. W.).—“Description of a nondescript species of the genus Con- 
dylura.” <Boston Journ. Philos, and Arts, ii, 1825, pp. 580, 583. (Also, Tillocli’s Philos. 
Mag., lxvii, 1826, pp. 191-193.) COUES ON INSECTIVOROUS MAMMALS. 
entially or in practice, by most authors. The only question is, how much 
to allow. It is also certain that the recognized species must be largely 
reduced in number, specific characters having been too often drawn from 
features which can be proven to not hold good. 
The study of these diminutive quadrupeds would be difficult under 
the most favorable circumstances; and the kind of material that reaches 
us increases the difficulty. The skins are for the most part indifferently 
or very poorly prepared, and unaccompanied by cleaned skulls; while 
neither these nor the smaller number of alcoholic specimens are, as a 
rule, accompanied by the data requisite for their satisfactory utilization. 
They are generally unmarked for sex (difficult or impossible to determine 
from dried preparations at least) or date of capture. Measurements of 
dried skins are never more than a pproximately correct, frequently give 
very fallacious results, and must always be taken with allowance for 
probable error. This, in the case of such small objects, gives rise to 
much uncertainty. The date of capture is a very important item ; for 
the seasonal changes of the pelage are evidently as decided as they are 
in the cases of animals better known in this respect, though terms 
expressive of length, fullness, softness, etc., of the fur continually 
recur in descriptive writing, without a hint as to what seasonal condi- 
tion may be in point. To render such terms available in diagnosis, the 
date of capture must be known. 
Similar remarks apply to the coloration. Color is unquestionably a 
good specific character in many or most cases, perfectly reliable within 
certain limits, or rather within limits still uncertain. Color-variation 
in this family is presented under three conditions (aside from purely 
individual variation in this respect), namely, with age or sex, with 
season, and with geographical distribution—none of which have hitherto 
received sufficient attention on the part of American writers. I am not 
aware that the first-mentioned variations have entered to any appre- 
ciable extent into the establishment and description of species; and I 
must confess my own very slight knowledge of the subject. Seasonal 
color variation f know to be much greater than has ever been practically 
recognized by our writers, most of whom seem to have never even sus- 
pected its extent. In the Arctic material before me are some very 
striking illustrations of this variability in color. Under certain condi- 
tions of the change of pelage, specimens normally coucolor or imper- 
fectly bicolor show a narrow dark stripe along the back, sharply de- 
fined against rich-colored sides, the resulting pattern of coloration 
being comparable as to sharpness of effect with the pelage of a Weasel 
during the change from the summer to winter coat. I hope to enlarge 
hereafter upon this subject, which is one that no author, so far as I 
know, has adequately presented. The geographical variation in color 
is a third point which demands careful consideration. My studies up to 
the present go to show a very interesting parallelism with the state of 
the case I have determined for other small Mammals, notably the Mice BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
and Gophers, and which my friend Mr. Allen lias admirably brought out 
in his studies of the Squirrels. In some cases, I find almost identical 
effects of climatic or other conditions upon the Shrews and the Mice of 
particular localities, by which they both acquire the same facies loci. 
Present indications are that the normal variability of the Shrews in 
size, shape, and color is not less than has been determined to hold good 
in various other families of Mammals. But our species have yet to be 
handled with full appreciation of this fact, and revised accordingly. 
Besides these general conditions of variability, there are some pecu- 
liar to Insectivora. The tail and lips, if not also the feet, are known to un- 
dergo extraordinary changes in connection with the rutting season. 
The remarkable swelling of the tail of the shrew-like Mole, Gondylura 
cristata, finds its representation, if in less degree, among the Shrews, 
associated with tumidity of other parts. These facts are known at large, 
yet their practical application in the discrimination of species has been 
too limited. The implication of all such terms as “ pachyurus77, “ longi- 
rostris”, “platyrhinus ”, must be cautiously accepted. 
The skull and teeth offer a ready means of throwing our species into 
genera and lesser groups, and no step in the study of the Shrews can 
be safely taken without examination of the cranial and dental characters. 
The skulls which come into our hands are very commonly mutilated or 
defective as to the back part, such is the fragility of the cerebral por- 
tions; but fortunately the rostral portion, including the jaw, is unusually 
strong for its size, and, with the teeth, is generally available for study. The 
dental armature of the Shrews is singularly powerful, far surpassing, in 
relative strength, that of the large Carnivores. 
Notwithstanding assertions of authors to the contrary, the number of 
the teeth of the Shrews is constant in the same species. Replacement 
of the temporary teeth is said to occur in the foetus 5 at any rate, speci- 
mens occur so young that the teeth are still encapsuled in membrane, 
which, nevertheless, show the normal adult number and permanent rel- 
ative position when this envelope is torn off. All the American Shrews 
hitherto known have either 32, 30, or 28 teeth. The number in the lower 
jaw is the same for all, namely, 12. The difference in the upper jaw oc- 
curs in the lateral7 teeth intermediate betweeu the large anterior inci- 
soi and the first molariform tooth. It has been wrongly supposed by 
at least one author that the Blarince and Sorices of 30 teeth were respect- 
ively the young of those of 32 teeth. In the case of the 30-toothed 
Sorex, the validity of the numerical distinction is curiously proven by 
the fact that it is not the minute tooth immediately preceding tlie large 
molariform premolar which is wanting, but one of the preceding pre- 
molars. The minute tooth is there still, but it is preceded by only 3 in- 
stead of 4 lateral teeth. In the new subgenus proposed beyond, in 
which there are but 28 teeth, it is the same premolar which is wan tin a1. 
We have no known white-toothed Shrews in America, like Crocidura 
aranea, though in our 28-toothed species the points of only a few anterior COUES ON INSECTIVOROUS MAMMALS. 
teeth are colored, and these but slightly. In all the rest, the teeth 
are heavily pointed with color, as in Sorex vulgaris of Europe, with 
which our Sorices of 32 teeth are strictly congeneric. This color is 
usually described as “chestnut”; it varies much in intensity, from piceous 
reddish-black, through rich burnt sienna, to quite light and bright red. 
The younger teeth appear to be the more heavily colored; they take 
color with their early development. Since, too, it is their points that 
are most heavily colored, wearing of the dentition gradually lightens 
the tint at the same time that it decreases its extent. 
The Shrews are remarkably voracious animals, like the Moles, requir- 
ing a large supply of food, and the ceaseless working of their jaws 
results in attrition of the teeth to such degree that the appearance is 
greatly altered with age. In extreme cases, the cusps of the molars, 
ordinarily so conspicuous, are entirely ground away, the premolars are 
reduced to mere stumps, while the fangs of the upper incisors and the 
curious denticulations of the lower incisors suffer quite as much. Teeth 
of the same or very closely allied species vary remarkably in their 
appearance as a whole, probably according to age ; the variation being 
(besides the actual shortening of the teeth) in the apparent set or “dip ” 
of the anterior teeth, the degree to which they are “ tiled ” or imbricated 
at base, aud in the obliquity with which the auterior incisors connive. 
The precise nature and purport of these obser ml differences in the same 
or closely allied species, aud the reliability of certain assumed specific 
characters thereby afforded, remain matters for further investigation. 
I may here allude, however, to the curious fact first poiuted out by 
Professor Baird, aud which I have verified, of the modification of the 
premolar dentition which the Western species collectively, as compared 
with the Eastern, have undergone. A striking peculiarity of all the 
Western species, no matter how diverse in other respects, is to have the 
“third premolar” decidedly smaller than the “fourth”; while, in all the 
species east of the Bocky Mountains (with one possible exception), 
the same tooth is as large as or larger than the other. Of the fact there 
is no question ; it may be observed in an instant, and is unmistakable. 
Its significance is another thing. Some of the Western species are 
scarcely distinguishable, if at all, from their respective Eastern ana- 
logues, except by this character, and they all show it. It is even re- 
peated in Neosorex navigator, as compared with N. palustris. What 
relation this condition bears to the Pacific fauna it is difficult to under- 
stand. We may practically recognize it in two ways: by giving it 
prominence as a leading feature, by which two groups of Sorex proper 
may be discriminated, or by reducing it to merely a secondary charac- 
ter of certain species, irrespective of geographical distribution. To pur- 
sue the former course would be to rather widely separate certain species 
hardly or not distinguishable except by this technical character; to 
adopt the latter alternative would be to ignore a generalization equally 
legitimate and curious, that may have important if unsuspected rela- 638 
BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
tions with the determination of faunal areas. At present, I am inclined 
to follow Professor Baird in the appreciation of this character. 
Certain other relative proportions of the anterior lateral teeth of the 
Shrews, which Professor Baird used as means of pushing the analysis 
of the species still further, seem to be of decidedly less applicability, 
even if they do not fall wholly within the limits of individual variation 
of particular specimens examined. These, therefore, I shall not bring 
into consideration of the question. 
I may add here that no American Shrew is known to possess fewer 
than 28 or more than 32 teeth, though various authors have miscounted 
from 26 to 36, in the one case overlooking a minute premolar, in the 
other counting the posterior cusp of the upper anterior incisor as a 
distinct tooth. Genera have been founded on each of these blunders. 
§ 4.—GEOGRAPHICAL DISTRIBUTION OF THE AMERICAN 
SPECIES OF SORICIDCE. 
Shrews have been commonly supposed, or tacitly represented, to be 
wanting in the warmer parts of America. Many years ago, however, 
J. E. Gray named two species of “ Corsira” from Central America, and 
I have specimens from different localities in Mexico and from Costa 
Rica, whence one* species has hitherto been described. No repre- 
* Blarina (Soriciscus) micrura, Coues. 
Corsira tropicalis, Gray, P. Z. S., 1844, . . . . , descr. nulld (fide E. R. Alston in epist.). 
Sorex micrurus, Tomes, P. Z. S., 1861, 279 (Guatemala, coll. Osbert Salvin). 
Hab.—Guatemala (Salvin). Costa Rica (Carmiol). 
This is a 30-toothed Blarina (subg. Soriciscus), very closely related to United States 
species like B. cinerea, B. exilipes, and B. berlandieri, if really distinct. As I have not 
finished my examination of the specific differentiation of this group, I should not here 
notice the supposed species were it not already described and did I not wish to indicate 
its proper generic and subgeneric position. 
A short time ago I sent a number of Shrews to my valued correspondent Mr. E. R# 
Alston, of London, begging him to compare them with the types of certain species 
preserved in the British Museum. I receive his answer just in the nick of time, as 
these sheets are passing the press. He identifies my British American specimens with 
types of Sir John Richardson’s species described in the F. B-A., so that this matter 
will be placed beyond dispute as soon as I get ready to use the important information 
thus kindly communicated by Mr. Alston. 
Among the Shrews sent to him was a specimen from Costa Rica (coll. J. Carmiol), 
of which he states:—“I have little or no doubt that it is the same as Sorex micrurus 
Tomes .... I have not access to Mr. Tomes’s types, but I have examined another of 
Mr. Salvin’s specimens, in spirits, and have no doubt your animal is the same. I also 
believe that Gray’s Corsira tropicalbs is the same, though the types look darker from 
dirt.” 
Mr. Alston writes further“ Gray’s C. iemhjas, afterward renamed in MS. C. teculyas 
is a large species, apparently a true Sorex . . . .” Not to anticipate the description of 
the species, which I trust we shall have from Mr. Alston in due time, I thus merely 
allude to the apparent presence of Sorex proper in Central America, as the Soricidce 
have not hitherto been ascertained to be represented there excepting by the genus 
Blarina, nor indeed south of the United States excepting by Blar ina and by the beyond- 
described new subgenus and species of Sorex. COUES ON INSECTIVOROUS MAMMALS. 
639 
sentatives of the Soricidce, or, indeed, of the order Insectivora, are known 
in South America. 
In North America, the differentiation of the Soricidce into genera and 
species has progressed farthest in the temperate and cold-temperate 
portions of the continent. Shrews occur throughout British America 
and the United States, from Atlantic to Pacific, and north to the very 
shores of the Arctic Ocean. These diminutive quadrupeds are endowed 
with wonderful powers of resisting cold, generating heat enough in their 
small bodies to endure the rigors of hyperborean winters. Their 
rapacity, voracity, and salacity are of the highest order, and they are 
incessantly active, never hibernating, but running freely about on the 
snow during the long Arctic winters. In the high north, the species are 
few, but individuals abound, comparable in numbers with the Arvicolas 
and Lemmings which swarm in the sphagnous regions of the Arctic zone. 
The genus Sorex alone is known to occur in the higher latitudes, where it 
is represented by the subgenera Sorex proper (one species being very 
near S. vulgaris itself) and Microsorex, the latter only just now ascer- 
tained to extend to the region of the Yukon Biver. 
Somewhat farther south, in Northern United States and contiguous 
portions of British America, the genera and species multiply directly. 
Here we encounter Neosorex, and with it or directly after it Blarina, the 
latter being the most characteristic American genus of the family. Spe- 
cies of Neosorex are known to occur from Nova Scotia and New England 
across to Washington Territory and Oregon, and south along the Bocky 
Mountain chains to New Mexico. It is not yet time to map its distribu- 
tion. I suspect that its dispersion is wider than now known. I anticipate 
its occurrence in Alaska and other northern regions, where the present 
evidence of its absence is wholly negative; but I rather presume that 
its southward extension may prove to be really limited much in the way 
just indicated. It seems to find its centre of abundance in interior cold- 
temperate regions, as those of the lied Iiiver of the North and the Great 
Lakes. 
Sorex proper occurs throughout the United States; at any rate, it can- 
not be supposed absent from any single area, so extensively is it repre- 
sented by specimens now in our hands. Three or more species are pe- 
culiar to the Pacific Province of the United States; others are generally 
dispersed, but most abundant in individuals in northerly portions of the 
United States, where also occur the majority of the species. Exclusive 
of the peculiar Pacific ones, all the described United States species occur 
in New England or along the northern tier of States, this being also the 
United States distribution of the single known species of the subgenns 
Microsorex (M. hoyi), though the entire distribution of the latter must 
not be presumed to be known as yet. 
The remarkable new subgenus Notiosorex, to be described on a suc- 
ceeding page, is found in New Mexico and at Mazatlan, Mexico ; it is, with 
one exception, the only representative of the genus Sorex known to occur 640 
BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
south of the United States, the subtropical extension of the family further 
being represented, as far as is now known, only by one or two species of 
Blarina, and by the still undescribed species of Sorex (?) named Corsira 
temlyas by Gray. 
Blarina, the genus of Soricidce which contains the most species 
among those peculiar to this continent, is on the whole rather southerly 
in distribution. It is not known to occur much beyond the northern 
border of the United States, nor has it been detected on the Pacific 
side. A species of Blarina proper (i. e., of Blarina with 32 teeth) is the 
commonest representative of the family in New England and adjacent 
portions, and with another species (or variety) extends more sparingly 
into a part at least of the Southern States. Westward, I have no speci- 
men of this subgenus beyond the plateau-region whence Say described the 
original u Sorex'1'1 brevicauda; but it probably reaches the Rocky Mount- 
ains at least. Blarina of 30 teeth is still more decidedly southerly. I 
am not aware that it is known north of the Middle States, and it appears 
to be the most abundant and characteristic representative of Soricidce 
in various South Atlantic States, as the Caroliuas and Georgia. One 
species (if not also a second) occurs throughout the Southern States, 
and extends through the Western States to Kansas and Nebraska, if 
not farther, and at least as far north as Council Bluffs. This same sub- 
genus, to be characterized beyoud as Soriciscus, extends through Mexico 
to Costa Rica, being represented south of the United States by at least 
two species. With the exception of one Mexican species of Sorex (Notio- 
sorex), and one Central American species, perhaps a true Sorex, it is the 
only known subtropical representative of the Soricidce. 
§ 5.—DETERMINATION OF THE AMERICAN GENERA AND 
SUBGENERA OF SORICID.fi. 
According to reliable authority, the Old World Shrews occur under 
three principal modifications, represented by as many leading genera 
and their respective intimate associates. These three are Sorex, Croci- 
dura, and Crossopus. 
Sorex, the most generalized type, is the only one which is known to 
occur in America. With its Old World subdivisions I am not familiar. 
Paradoxodon and Soriculus appear to be the most prominent. The 
American species of Sorex are nearly all strictly congeneric with Sorex 
vulgaris* having 32 colored teeth. I am uncertain to which one, if to 
any one, of the subdivisions the type Microsorex of 30 colored teeth may 
belong. We have nothing in America exactly like Grocidura (type C. 
aranea) of 28 uncolored teeth; but the new subgenus Notiosorex, of 28 
nearly colorless teeth, large naked ears, etc., seems to answer for this 
type. Crossopus, embracing the Old World Water-shrews of 30 colored 
\\ liich I here consider the type ot Sorex, though some authors restrict the name to 
a species with white teeth (Hydrosorex Duv., 1834). COUES ON INSECTIVOROUS MAMMALS. 
teeth, large fringed feet, and long keeled tail, finds its strict representa- 
tive in the American genus Feosorex, which includes equally aquatic 
species, with large fimbriate feet, though the tail is scarcely carinate 
w ith hairs, and the teeth are 32 in number.* 
Blarina with its several species is the most characteristic American 
genus, and the most prominent of those peculiar to this continent, hav- 
ing no exact Old World analogue. It is vrell marked by the structure 
of the small external ears, invisible on ordinary inspection, very short 
tail, and a special condition of the dentition, although the number of the 
teeth, 32 or 30, is the same as iu Sorex. Like the latter, it is divisible 
into subgenera, according to the number of the teeth ; Blarina proper 
(type brevicauda) having 32 teeth, while there are but 30 in the section 
Soriciscus, defined beyond. 
Following are the diagnostic characters of the American genera and 
subgenera of Soricidee, with their respective synonyms :— 
I. Genus XEOSOBEX, Baird, 1857. 
Sorex, sp., Ricn., F. 13.-A., i, 1829, 5. (S. pahistris, orig. descr. in Zodl. Jonrn., iii, No. 
xii, April, 1828, 517. Teeth miscounted 30 instead of 32, the true number.) 
Neosorex, Bairo, M. N. A., 1857, 11. (Type N. navigator Cooper, sp. n.) 
Hgdrogale, Gill, Bull. U. S. Geol. and Geogr. Surv., 2d ser., No. 2, 1875, 111. (Not of 
Pomel, 1848, which is a figment, based on a blunder.) 
Chars, gen.—Teeth 32 (f|), as iu Sorex proper. Upper uniciispidst 
5, the fifth minute, the fourth and third smaller than the second and 
first, which are equal to each other; third equal to or smaller than 
fourth. Upper incisors with a posterior hook as large as the succeed- 
ing tooth, and like it in shape, and with a notched lobe on the inner 
side, connivent with its fellow. Lower incisors with several (normally 
three) denticulations on the cutting edge, and reaching back beyond 
the next tooth, which is thus entirely above them. Teeth all colored* 
* Dr. Gill having recently proposed to supplant the term Neosorex Baird, 1857, by 
Hydrogale Pomel, 1848, it becomes expedient to inquire into the case. Hydrogale was 
based upon Sorex fimbripes of Bachman—a species which has occasioned much uncer- 
tainty and confusion. The name suggests an aquatic species; but this is altogether 
erroneous. In 1861, Baird examined Bachman’s type preserved in the Philadelphia 
Academy, and found it to be a species of ordinary 32-toothed Sorex, scarcely or not 
distinguishable from “cooperi”. Bachman miscounted 34 teeth (which number no 
known American species possesses), and wrongly laid stress on certain characters of 
the feet, which had no basis except in the accidental condition of the specimen as 
preserved. Hydrogale is therefore based on a misapprehension, the characters assigned 
having no existence in nature, and the type of the “genus” being scarcely or not spe- 
cifically separable from a previously known form ; it therefore becomes of course a 
synonym of Sorex proper, as a pure figment—so far is it from being “ undoubtedly con- 
generic with Neosorex”, as assumed by Dr. Gill without that degree of caution which 
distinguishes that trained naturalist. 
t By the descriptive term “unicuspids”, I iuteud to cover in these descriptions the 
anterior series of lateral teeth between the bicuspid front incisor and the pluricuspid 
molariform teeth, purposely avoiding committal to the homologies which would be im- 642 
BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
Rostral part of skull very slender and attenuate, with nearly straight 
and horizontal upper profile far out of line with the profile of the swollen 
cerebral part. Iuterorbital constriction at the maximum. Bridge over 
the anteorbital foramen comparatively narrow. Coronoid process of jaw 
slender, tilted forward ; angular process comparatively short, extremely 
slender, and nearly horizontal. Tail scarcely or not shorter or much 
longer than the head and body, without a decided keel of hairs along 
the under side. Ear distinct, the auricle directed backward (as usual). 
Feet large, fringed with long, straight, stiffish hairs in regular series; 
the hinder feet especially well developed and natatorial, about one-fourth 
as long as the head and body. Pelage long, soft, and thick, to resist 
water. Of large size and highly aquatic habits. 
Type.—Neosorex navigator Cooper. Peculiar to North America, where 
it replaces Crossopus of the Old World. Includes the Water-shrews of the 
Western Hemisphere. Although the strict representative of Crossopus, 
it differs decidedly from thelatter in cranial, dental, and external charac- 
ters. In Crossopus there are but 30 teeth, the unicuspids being only 4, 
the three anterior ones regularly graduated in size, the fourth minute ; 
the upper incisors appear to lack the lobe on the inner edge, the posterior 
hook is smaller, and the under incisors have but one denticulation (in 
the only specimen before me). The skull is much broader, as shown 
especially between the orbits and at the interpterygoid space. The con- 
tour of the palate is more broadly pyriform ; the rostral part of the 
skull is much less attenuate, with wider bridge over the anteorbital 
foramen. The mandible as a whole is stronger, with stouter, more 
nearly perpendicular, coronoid process, and more oblique angular pro- 
cess. The tail has a prominent keel of stiffish hairs along the under 
side, not developed in Neosorex. I am unable to compare the ears. The 
feet are very similar, though the fimbriation is less conspicuous. In 
general appearance, Neosorex navigator and N. pal.ustris are quite like 
Crossopus fodiens, all these Water-shrew's being large, long-tailed, large- 
footed species, sharply bicolor, blackish above and whitish beneath. 
plied iu the use of the term “ premolars ”, applied by Bail’d to these teeth. The Shrew’s 
teeth are conveniently separable, for purposes of ordinary description, into three sets, 
namely:—(1) The enlarged and peculiarly modified single incisor, on each side, above 
and below ; (2) A series of varying number of small unicuspid teeth, intervening be- 
tween the incisors and the molariform teeth ; (3) The molariform teeth, always four 
above on each side and three below on each side. The anterior one of these last on each 
side above is homologically a premolar, though it is like the true premolars in appear- 
ance ; the homologies of some of the uuicuspid teeth are iu question. All the American 
Soricidce (like all the Shrews as far as known) have the same number of under teeth, 
namely, 12. The differences in the number of the teeth arise from the presence of 3, 4, 
or 5 “unicuspids”. The following formula covers the numerical composition of the 
teeth of all American shrews, without being committed to their homologies :— 
1—1 . 3—3 or 4—4 or 5—5 4—4 16 or 18 or 20 no on on 
+ — + 3H3 = S = 28 0>- 80 or 32. 
Incisiforra. Laniariform. Molariform. COUES ON INSECTIVOROUS MAMMALS 
643 
All are highly aquatic, comparing with the species of Sorex and Bla- 
rina as a Mink or Otter does with most Mustelidce, or as a Muskrat with 
ordinary Arvicolce. 
To the type-species is to be added the Sorex palustris of Richardson, 
and possibly another species. 
II. Genus SOREX, Linn. 
(а) 
Sorex, Linn. (Type S. vulgaris, fideNathusius, Arch. f. Naturg., 1838, 45.) 
Sorex of Authors referring to S. vulgaris (not of those applying the name to Crocidura 
aranea). 
Corsira, Gray, Proc. Zool. Soc., 1837, . . . (Type . . .) 
Otisorex, De Kay, Zool. N. Y., 1842, . . . (Type 0. platyrhinus.) 
Hydrosorex, Duvernoy, 1836, nec 1834. 
Amphisorex, Duvernoy, 1834, nec 1836. • 
Hydrogale, Pomel, . . . 1848. (Type S. fimbripes Bach. Genus based in error.) 
(б) 
\ 
Paradoxodon, Wagner, . . . 1855. (Separate subgenus.) 
(c) 
Soriculus, Wagner, . . . 1855. (Separate subgenus.) 
(d) 
Microsorex, Baird, MSS., 1861. (Separate subgenus. Type S. hoyi Bd.) 
(«) 
Notiosorex, Baird, MSS., 1861. (Separate subgenus. Type S. crawfordi Bd. n. sp. infrA) 
In the present uncertainty which obtains respecting the limitation of 
the original Linnaean genus, I do not attempt to give a diagnosis cov- 
ering all its modifications. Its value is very differently rated by authors, 
some confining the term to S. vulgaris and its strict congeners, while 
others, even among the latest systematists, make the genus coextensive 
with the family, as Peters and Mivart* have done. I think that the 
genus may be most naturally defined to exclude Crossopus and Croci- 
dura with their respective allies, and Blarina, making subgeneric sec- 
tions according to the numerical composition of the teeth, though some 
of the forms included in the foregoing synonymy may be worthy of full 
generic rank. It will tend to prevent confusion to hold 8. vulgaris as 
the type. 
To the genus Sorex, as thus rigidly restricted, belong nearly all the 
* According to the latter author, the constants of the teeth of Soricidce are as fol- 
lows :— 
. — 1-1 — 3-3 
•• l=T’c- Hi^m-Hi’m-3=3; 
the variables being confined to the upper incisors and upper premolars, which may be 
either 
«• *± pm. *4-, ori. 3-±, pm. or i. ?±, pm. or iM, pm. hi. 
8 B H 644 
BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
American species, and it is the only Old World type found in this 
country, Grossopus being replaced by Neosorex, and Groculura having no 
exact analogue, though the new subgenus Notiosorex may be considered 
to answer to it. 
Among our numerous species of Sorex, however, is found considera- 
ble diversity of external characters, coupled with difference in the nu- 
merical composition of the teeth, enabling us to mark off three sections 
with ease. The teeth are either 28, or 30, or 32, according to the num- 
ber of upper unicuspids, whether 3, or 4, or 5. Other distinctions may 
be drawn from the relative proportions of the unicuspids and from cer- 
tain conditions of the tail, feet, and ears. 
The species of American Sorex at large offer the following characters:— 
Body slender, head elongate, and muzzle attenuate; breadth of the 
head nearly or about half its length; muffle naked, with a terminal 
vertical furrow continuous with the horizontal one formed below by 
meeting of the lips, i. e., end of the snout bilobate; nostrils lateral; 
whiskers long, some of them reaching beyond the head; ears large 
(comparatively), with auricle directed backward (as usual); the ante- 
tragus elliptical or semicircular, fitting and closely applied to the meatus, 
its upper root passing beneath a second transverse nearly horizontal 
flap, which projects forward and forms a second valve, closing the 
remaining portion of the naked auditory region. Both faces of these 
flaps are generally naked, the anterior always so ; both surfaces of the 
auricle are thinly haired, while its edge and the edges of both the flaps 
are fringed with long hairs. The fore feet are from one-lialf to two- 
thirds as long as the hinder ones ; both are naked below; the sides of 
the heels, however, are hairy, leaving only a narrow strip bare. The 
soles are paved with small granulations, among which are six large 
tubercles, oue at the base of respectively the first, second, and fifth 
digits, one common to the bases of the third and fourth, and another 
on each side of the sole midway between the heel and the bases of the 
digits. The feet are not fimbriate in the sense that those of Grossopus and 
JSeosorex are. The tail is generally subequal to the trunk aloue, so ne- 
times, however, about as long as the head and body ; in only one 
instance known to be less than half this latter dimension. It is more 
or less thickly, but uniformly, covered with hairs, which usually form a 
slight pencil at the tip; but under some conditions, probably seasonal 
or otherwise fortuitous, the tail is nearly naked. 
The skull is slender, constricted behind the molars. The upper 
unicuspids are 3, 4, or 5. When 3, they are regularly graduated in 
size, none being very small. When 4, the first three are graduated 
in size, the fourth being abruptly smaller and very minute, scarcely 
visible from the outside, and liable to be overlooked, so crowded is it 
between the closely approximated or even touching teeth which 
precede and follow it. When 5, the first four are abruptly larger COUES ON INSECTIVOROUS MAMMALS. 
645 
than the minute fifth, which occurs under the same conditions as last 
described ; among the larger unicuspids there is either regular grada- 
tion in size, or oftener the two first are coequal and larger than the 
third and fourth, or again the third is decidedly smaller than the 
fourth or second. In the species with 30 or 32 teeth, these conditions 
are contrasted with those occurring in Blarina of the same numbers 
of teeth; for in the latter the last two or three unicuspids are always 
smaller than the first two, and much crowded. The large upper in- 
cisor has a notched lobe or snag on its inner face, besides the strongly 
developed posterior hook, which looks like a separate tooth, and 
closely resembles the succeeding tooth. The under incisor has one, two, 
or three denticulations on its cutting-edge, and reaches so far back 
that the next tooth is entirely above it, while more or less of the suc- 
ceeding tooth is likewise similarly placed with reference to the incisor. 
The teeth are always colored (as they are also iu Neosorex and Bla- 
rina), but in one subgeuus the coloration is very slight. 
Such sum of characters is offered under three modifications (of the 
teeth more particularly), which must be made the basis of subgeueric dis- 
tinction, if not to be more highly appreciated. These are as follows:— 
a. Subgenus Sorex, L. (emend). 
Chars, subg.—Teeth 32 (f&). Upper unicuspids 5; the fifth minute, 
but generally visible from the outside, though crowded between the 
preceding unicuspid and the first molariform tooth, which are not in 
contact; the first and second appreciably larger than the third and 
fourth, which latter vary in size relatively to each other. Interior snag 
and posterior hook of upper incisor well developed; lower incisor with 
(normally) three denticulations ; whole of next tooth and half of the next 
placed above incisor. Teeth all well colored. Coronoid of jaw long and 
comparatively slender, nearly vertical. Skull moderately high behind, 
the profile of the cerebral portion rising out of liue with that of the 
rostrum ; depth of rostrum (including closed jaw) less than that of cer- 
ebral portion of the skull. Molar dentition moderate in development; 
distance across outer edges of molars not over half the width of the 
cranium; length of series of molariform teeth not more than half the 
length of the whole line of teeth. Tail not less than half the length of 
the head and body, usually longer than the trunk alone. Central line 
of heel naked. Ears moderately large. 
Type.—Sorex vulgaris, with which most of the American Sorices are 
strictly con-subgeneric. 
Group A.—Species with the third and fourth unicuspids approximately 
equal in size (both smaller than the first and second). 
Group B.—Species with the third unicuspid decidedly smaller than the 
fourth (which is itself less than the second and first). (Confined to 
the Pacific Province.) 
[Subgg. 6 and c not American.] 646 
BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
d. Subgenus Microsorex, Baird, MS., 1861. 
Chars subg.—Teeth 30 (U|). Upper unicuspids 4; the fourth mi- 
nute, concealed from view externally by the contact of the third uuicuspid 
and first molariform tooth; the third appreciably smaller than the second 
and first, which are equal to each other and to the hook of the incisor. 
Interior snag and posterior hook of upper incisor well developed ; lower 
incisor with (normally) two denticulations, and extending so far back 
that the two succeeding teeth are placed entirely above it. Teeth all 
well colored. Coronoid process of jaw long and comparatively slender. 
Molariform teeth large; distance between their outer edges more than 
half the width of the skull. Depth of rostrum (including jaw) greater 
than that of the cerebral portion of the cranium. Series of molariform 
teeth longer than half the length of the whole series of teeth. External 
characters not obviously different from those of Sorex proper. Tail 
about as long as trunk. 
Type.—Sorex hoyi Baird, from which S. thompsoni does not appear to 
be specifically distinguishable. 
This perfectly valid section of Sorex has been suspected to rest upon 
immature dentition, the decrease in the number of teeth being supposed 
due to suppression or non-development of the minute last uuicuspid. 
But it will be seen from the foregoing that this minute tooth, immedi- 
ately preceding the first molariform tooth, is present in both cases, being 
in Sorex proper preceded by four larger unicuspids, while in Microsorex 
the unicuspids preceding it are only three in number. 
e. Subgenus Notiosorex, Baird, MS., 1861. 
Chars, subg.—Teeth 28 (f§); upper nnicuspids3, the minute last uni- 
cuspid of Sorex proper and Microsorex here wantiug; first aud second 
unicuspids about equal to each other, larger than either the third 
unicuspid or the posterior hook of the incisor. IsTo internal suag or 
notch on upper incisor, and the posterior hook only moderately devel- 
oped, being smaller than the succeeding tooth. Lower incisor with only 
one denticulation, or merely a slight sinuation ; its tip hooked upward, 
its base reaching below the two succeeding teeth. Teeth scarcely colored, 
and only on the tips of the incisors and a few succeeding teeth, the 
molariform ones left white. Coronoid process of jaw comparatively 
short, obtuse, and widely diverging outward. Proportion of molariform 
teeth to the rest of the series and width across them relative to the 
cranial width as in Microsorex. Skull very low behind, broad across 
the orbits, and comparatively little attenuate in front. Ears remark- 
ably large, thinly haired, and conspicuous. Tail short, somewhat as in 
Blarina, scarcely or not half as long as the head and body. General 
external appearance of Crocidura. 
Type.—Sorex (Notiosorex) crawfordi Baird, MS., 1831, sp. u., described 
at length beyond. COUES ON INSECTIVOROUS MAMMALS. 
647 
This remarkable new submenus, the only one of America possessing 
28 teeth, is related to Grocidura, having the same number of teeth as 
G. aranea, and sharing other deutal characters, such as absence of in- 
ternal snag and small size of posterior hook of the upper incisor, single 
or obsolete denticula'tion of the under incisor, massiveness of the teeth, 
and particularly of the molars, relative length of the molariform series 
to the whole line of teeth, etc. The teeth of Grocidura are entirely 
white, of Notiosorex scarcely colored. In both, the skull is lower behind 
than in Sorex proper, much less constricted across the orbits, and much 
less attenuate anteriorly, while the coronoid process of the jaw is 
shorter, stouter, and more divergent from its fellow. 
The type of Notiosorex is in very bad order, not permitting satisfac- 
tory examination of external characters. A dried specimen of Notioso- 
rex from Mazatlan, apparently a second species of the group, is in ex- 
cellent condition. This is strikingly similar to Grocidura in general 
external appearance, even to the large scant-haired ears and short tail. 
The size is about the same, while in coloration it is scarcely distinguish- 
able from some Bavarian specimens of Grocidura labeled l(S. leucodon 
Hermann”. 
III. Genas BLARIXA, Gray, 1837. 
Sorex, 8pp., Auct. Amer. 
Blarina, Gray, Proc. Zool. Soc. Lond., 1837. (Type Sorex talpoides Gapper.) 
Brachysorex, Duvernoy, Mag. de Zool., 1842. 
Talpasorex, Pomel, . . . 1848. (Nec auct.) 
Cryptotes, Pomel, . . . 1848. 
Anotus, Wagner, . . . 1855. 
(a) 
(&) 
Sorici8cus, Coues, infra, subg. n. (Type Sorex parvus Say or S. cinereus Bachm.) 
Chars, gen.—Teeth 32 (f|) or 30 (if). Upper unicuspids either 5 or 4, 
the two anterior of which are abruptly larger than the two or three pos- 
terior ones, which latter are small and much crowded. When there are 
5 unicuspids, the third and fourth are subequal to each other; in any 
case, the fifth is minute, much smaller than any preceding one. The larger 
unicuspids have supplementary cusps. Upper incisors without internal 
snag or notch, and rarely connivent, with greater or less development 
of the posterior hook. Under incisor with several obtuse denticula- 
tions, or nearly sinuate, extending backward a variable distance, accord- 
ing to the subgenera. Skull variable in massiveness, etc., in the same 
way. Teeth all colored on the points. Coronoid process of jaw com- 
paratively short, stout, and erect (rather inclined forward as well as out- 
ward, as in Sorex and its subdivisions). Styliform angular process of jaw 
very short, scarcely or not reaching as far back as the condyle. Tail 
short, scarcely or not as long as the head, uniformly haired, with a small 648 
BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
terminal pencil. External ears small, invisible on ordinary inspection, 
and peculiarly constructed; the auricle, as well as other parts, being 
directed forward to close the meatus, leaving no opening or appearance 
of a concavity of auricle. Fore feet broad, large in comparison with the 
hinder ones, the palms naked, the claws enlarged and somewhat fos- 
sorial, longer than the hind claws. Hind feet very small comparatively, 
the soles granular and pluri-tuberculate, the heels hairy, excepting 
usually a very narrow central strip. Body stout; size variable, the 
species ranging from much the largest to the smallest of American 
Shrews; coloration either uniform or sharply bicolor. 
The short-tailed or so-called “earless” Shrews of America constitute 
a strongly marked group not represented at all in the Old World. They 
are readily recognized by the characters of the tail and ears; while the 
skull and teeth furnish equally or more satisfactory means of discrimina- 
tion from any other genus of Soricidce. fn the foregoing diagnosis I only 
present the more salient cranial and dental characters, serving for 
ready determination, omitting here, as elsewhere in this paper, many 
details, which, however necessary in full description, would, if here intro- 
duced, tend to obscure the characters I wish to set forth prominently. 
Nevertheless*, I am obliged to define the genus somewhat loosely, 
owing to the dissimilarity of the two types of form it covers. So far 
from there being only one species of Blarina, as Mr. Allen has sought 
to maintain, there are a number of them, representing two subgenera as 
distinct as any of those just established in the genus of Sorex, if not 
more so. Erroneous statements respecting the ears, and miscounts of 
the number of the teeth, which have been rated as many as 34 and even 
36, have aleady caused the erection of several groundless genera, such 
as Anotus and Cryptotis; but all these, as Baird has remarked, are 
strictly synonymous with Blarina of Gray or Bracliysorex of Duvernoy, 
and belong to the section with 32 teeth represented by B. talpoides. 
The other section, of 30 teeth, properly characterized by Baird in 1857, 
but not hitherto named, I propose to call Soriciscus. It is the only 
known representative of the genus in Mexico and Central America. 
a. Subgenus Blarina, Gray (emend.). 
Ohars. subg.—Teeth 32 (f§); upper unicuspids 5 ; the two anterior 
ones largest, subequal to each other, exceeding in size the hook of the 
incisor ; next two abruptly smaller, subequal to each other; last one 
smaller still, very minute, scarcely or not visible externally ; three last 
appearing crowded together. Upper incisor with the posterior hook 
reduced to a mere rectangular lobe, much smaller than the succeeding 
tooth. Lower incisor reaching back below the first molar, so that two 
teeth and part of a third are above it. Skull comparatively massive 
with well developed lambdoidal and sagittal crests, the former defining 
an occipital plane. Very little interorbital constriction, and rostral 
part of skull moderately tapering, not nearly so attenuate as in Sorex. COUES ON INSECTIVOROUS MAMMALS. 
649 
Upper profile of skull nearly in one line from end of nasals to occiput. 
Size from medium to largest. Fore feet at maximum of size, with larg- 
est claws. Coloration nearly uniform. 
Type.—Sorex brevicauda Say or S. talpoides Gapper. 
b. Subgenus Soriciscus, Coues, snbg. n. 
Chars, subg.—Teeth 30 ; upper unicuspids 4 ; first two largest 
and subequal to each other ; third abruptly smaller; fourth smaller still, 
very minute and usually crowded out of view externally. Upper incisor 
developing a decided posterior hook, nearly or quite as large as the suc- 
ceeding tooth, and much as in Sorex itself. Lower incisor reaching 
back only below the second succeeding tooth, so that only one tooth and 
part of a second are placed above it. Skull in general more like Sorex 
than like Blarina proper; sagittal and lambdoidal crest obsolete, the 
occiput rounding insensibly into the parietal walls. Interorbital con- 
striction and attenuation of rostrum much as in Sorex. Upper profile of 
skull straight in front, rounding up behind, nearly as in Sorex. Size 
small to very small. Forefeet relatively smaller than in Blarina proper, 
with less developed claws. Coloration indifferently bicolor or coucolor, 
ofteuer the former. 
Type.—Sorex parvus Say or S.cinereus Bachm. 
Here belong the greater number of the species, among them the very 
smallest Shrews of America. In bulk of body, some species are about 
the same as Microsorex hoyi, but the shortness of the tail makes the 
total length much less. Thus, apparently full-grown specimens be- 
fore me are under two and a half inches long, tail and all, while M. hoyi 
measures at least three inches, tail included. In general configuration, 
the skull is more like that of an ordinary Shrew than it is like that of 
the other section of the same genus. 
I conclude this portion of the subject with an analysis of the genera 
and subgenera according to a few salient features:— 
A. —Ears ordinary. Feet fimbriate. Tail about equaling or exceeding 
the head and body in length. 
Teeth 32 . Neosorex. 
B. —Ears ordinary. * Feet ordinary. Tail shorter than head and body. 
Teeth 32 Sorex. 
Teeth 30 Microsorex. 
Teeth 28 Notiosorex. 
C. —Ears peculiar. Feet not fimbriate. Tail about as long as the head. 
Teeth 32 Blarina. 
Teeth 30 Soriciscus. 650 
BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
§ 6.—DESCRIPTION OF FIVE NEW SPECIES OF AMERICAN 
80RICIDM. 
1. Sorex pacificus Baird, n. sp. 
Sorex pacificus, Baird, MSS. ined., 1861. 
Teeth 32. Upper unieuspids 5, the third decidedly smaller than the 
fourth, the fifth smaller still, but distinctly visible externally. Upper 
incisor lacking an obvious internal notch, but with well developed pos- 
terior hook as large as the succeeding tooth. Under incisor with two 
blunt lobes and a slight sinuation, reaching back to first molar, two 
teeth being placed entirely above it. 
Nearly unicolor, without line of demarkation, becoming insensibly a 
little paler below. Rusty iron-gray, or light dull reddish-brown, gradu- 
ally fading to a lighter grayer shade of the same on the under parts. 
Feet and under side of tail brownish-white; tail more decidedly bicolor 
than the body, colored above to correspond. Teeth colored as usual. 
Large; length (of skin, approximate) 3.00 inches. Tail-vertebrae 2.25, 
with hairs 2.45. Hand 0.35. Foot 0.60. 
Hab.—Fort Umpqua, Oregon (Dr. E. P. Yollum). 
Type No. 3266, Nat. Mus. (Smiths. Inst.). 
Readily distinguished by the peculiar proportions of the unicuspid 
teeth, which are as in all the other Shrews of the Pacific Province—these 
species being entirely different in other respects. One of the largest 
species, rather surpassing the 8. 11 richardsoni” of Baird, and two or 
more times as bulky as any of the Shrews like ucooperin or “platyrhinus”. 
Nearly identical in color with the type of 8. “ richardsoni” of Baird (No. 
830, Nat. Mus., Racine, Wis.), but larger; tail an inch longer, differing 
in the latter respect much as Neosorex navigator does from N. palustris. 
Requiring no comparison with any other species hitherto described. 
2. Sorex sphagnicola Coues, n. sp. 
Teeth unknown; undoubtedly 32 ; with third unicuspid undoubtedly 
not smaller than fourth. 
Nearly unicolor, without line of demarkation, merely paler below; 
blackish-brown, changing insensibly on under parts to blackish-gray, 
with a slight rusty shade; tail obscurely bicolor, to correspond; feet 
dark brown. 
Very large, fully equaling 8. u alpinus” of Europe; length (of skin, 
approximate) 3.25 ; tail only about half as long, 1.50 ; foot 0.50. 
Hab.—Fort Liard, H. B. T., or vicinity (W. L. Hardisty). 
Type No. 6361, Nat. Mus. (Smiths. Inst.). 
Belonging to the group of large whole-colored species, of which 8. 
pacificus and 8. u ricliardsoni ” of Baird are other members, and which 
represent the large plumbeous whole-colored 8. “ alpinus ” of Europe. 
General appearance that of Blarina talpoides, being sooty-blackish and 
as large as many specimens of the latter. Distinguished from S. “ rich- COUES ON INSECTIVOROUS MAMMALS. 
651 
ardsoni ” of Baird by superior size and fuliginous coloration; from S. 
pacificus by the same points in which 8. richardsoni differs, tail an inch 
shorter, etc. 
3. Sorex (Notiosorex) crawfordi Baird, n. subg. et sp. 
Sorex (Notiosorex) crawfordi, Baird, MSS. iued., 1861. 
Teeth 28; upper unicuspids 3; third a little smaller than second and 
first; upper incisor without internal notched lobe, the posterior hook 
smaller than the next tooth ; lower incisor reaching below the two suc- 
ceeding teeth, its cutting edge nut denticulate, merely sinuate ; denti- 
tion as a whole very heavy, the teeth uncolored, except points of a lew 
anterior ones. Head large. Tail short; little over half as long as head 
and body. 
Color “light chestnut-brown, paler beneath”. Yery small; length 
(alcoholic) 1.90; tail-vertebrae 1.10, with hairs 1.15; hand 0.25; foot 
0.40; tip of nose to incisors 0.11, to eye 0.40, to occiput about 0.80; 
length of skull 0.08, its width 0.31, its height 0.18; width at interorbital 
constriction 0.17. 
Hah.—Fort Bliss, New Mexico, or vicinity (Dr. S. W. Crawford, U. 
S. A.). 
Type No. ffff? Mus. (Smiths. Inst.); specimen in alcohol 2653; 
prepared skull 4437. 
In further elucidation of this interesting form, I quote passages from 
Professor Baird’s original MS.: — 
“ It is much to be regretted that the only known specimen of this species 
is in exceedingly bad condition. There is enough, however, to show its 
strongly-marked distinction from any other North American species 
.... The muzzle is wider than usual in our small Shrews, owing to the 
size of the molar teeth ; the head, too, appears disproportionately large. 
The skull is very large for the size of the animal, measuring nearly 0.70; 
the rostral part is broad, and the interorbital constriction slight; the 
greatest width of the upper jaw is more than half as much as that of 
the cranium. The coronoid process of the mandible is short and stout. 
The molar teeth are of enormous size. Thus the middle of the ante- 
orbital foramen falls over the line of separation of the first and second 
molars [i e., molariform teeth], and the molar series is nearly two-thirds 
as long as the whole line of teeth. The upper incisor has no inner 
lobe or spoon-shaped expansion, resembling that of Blarina in this 
respect. There are but three upper premolars [i. e., unicuspid teeth]; 
all compressed transversely, forming a trenchant edge, the lateral out- 
line pointed. The 1st and 2d premolars are equal and larger than 
the 3d, which exceeds the posterior hook of the incisor. The lower 
incisor has no lobes, though the point is hooked upward and the upper 
outline sinuous. It extends backward to the 1st molar, the 1st and 
2d premolars being entirely above it; the latter have each a single 
cusp. The teeth are entirely colorless, except a slight chestnut tinge to 
the tips of the incisors and still less on the anterior premolars. BULLETIN UNITED STATES GEOLOGICAL SURVEY. 
“ The ears appear to be much as in 8. cooperi and its allies, and larger 
than in 8. hoyi. The 5th hind claw reaches half-way over the penul- 
timate phalanx of the 4th digit. The heels appear to be hairy behind, 
without a central linear naked space. The hairs at the ends of the toes 
appear of unusual length, extending beyond the claws. The color, as 
far as the hair remains on the alcoholic specimen, is a nearly uniform 
rufous, rather paler beneath ; the fur is long.” 
4. Sorex (Notiosorex) evotis Coues n. sp. 
Teeth 28, and dentition otherwise substantially the same as that of H. 
crawfordi. (Lower incisor with one decided lobe, not seen in N. crawfordi, 
but the difference may be due to age of the teeth, a supposition 
which the more decided coloration of the points of several anterior 
teeth of N. evotis tends to confirm.) 
Bicolor, but not very sharply so. Above, clear light brownish cine- 
reous, with a decided hoariuess; below, cinereous-gray, with scarcely a 
shade of rusty. Tail colored to correspond. Feet brownish-white. Claws 
and most of the whiskers colorless. The coloration is very nearly 
that of some specimens of Grocidura u leucodon ”, but rather more cine- 
reous above, and less distinctly bicolor. 
Tail very short, almost Blarina-like; rather scant-haired, with slight 
terminal pencil, scarcely or not one-third as long as head and body, 
and about equaling the head alone. Snout not peculiar. Ears ex- 
tremely large, scaut-liaired, conspicuous in the fur of the parts, recall- 
ing Grocidura ; structure, however, as well as can be judged, not pecu- 
liar. Soles naked to the heels along a narrow liuear strip. Pelage 
short, close, and sleek. 
Length (of a well-prepared skin, closely approximate) 2.90. Tail-ver- 
tebrae 0.90, with hairs 1.00. Hind foot 0.45. Fore foot 0.25. Snout to in- 
cisors about 0.15; to angle of mouth 0.30; to eye 0.45 ; to ear 0.80 ; to 
occiput 1.00. 
Hal).—Mazatlan, Mexico (F. Bisclioff). 
Type No. 9066, Nat. Mus. (Smiths. Inst.). 
The condition of H. crawfordi does not permit entirely satisfactory 
comparison; but the material, so far as it goes, indicates specific dis- 
tinction. The type of crawfordi is certainly adult, as shown by the 
teeth, hence its smaller dimensions are not attributable to immaturity. 
The more salient points of difference may be contrasted as follows : — 
N. crawfordi.—Length 1.90; tail-vertebrae 1.10 ; foot 0.40 ; tail about 
as long as trunk. Color “ light chestnut-brown, paler beneath”. 
N. evotis.—Length 2.90 ; tail-vertebrae 0.90 ; foot 0.45 ; tail about as 
long as head. Color lioary brownish-cinereous, ashy-gray beneath. 
5. Blarina (Soriciscus) mexicana Baird, n. sp. 
Blarina mexicana, Baird, MSS. ined., 1861. 
Teeth 30; upper unicitspids 4; first and second equal to each other 
and largest, exceeding a little the posterior hook of the incisor; third COUES ON INSECTIVOROUS MAMMALS. 
653 
abruptly much smaller (only about half as large); fourth minute, con- 
cealed from external view by contact of third with the first inolariform 
tooth. Posterior hook of upper incisor well developed, larger than third 
unicuspid; no internal snag. Under incisor with two prominent lobes, 
reaching back below the two succeeding teeth. Teeth all well colored; 
the points of the incisors quite black. 
Unicolor; entirely sooty blackish-brown, merely a little paler below, 
without any line of demarkation whatever; tail and feet likewise dusky. 
Tail rather long for Blarina, contained only two and a half times in 
length of head and body ; very scant-haired. Claws rather large. Fur 
soft and full, almost fluffy, with very little lustre. 
Length (of well-prepared skin, closely approximate) 2.50. Tail 1.00; 
the terminal pencil hardly 0.10 longer. Hands 0.35. Feet 0.50. Long- 
est claws 0.08 or 0.09. Skull (slightly defective behind, estimated) 0.75 ; 
its width 0.37 ; its height 0.25. 
Ilab.—Xalapa, Mexico (E. Montes d’Oca). 
Type Xo. ffff, Nat. Mus. (Smiths. Inst.) (skin 3525, skull 4438). 
This remarkable species combines the 30 teeth of Soriciscus and 
other dental characters of that group with the external appearance of 
Blarina proper, resembling B. talpoides in its uniform blackish color, 
though it is still darker, as well as much smaller. The tail is relatively 
longer, though the dimensions above assigned may be somewhat too 
large. The skull is heavier and less attenuate than usual in Soriciscus, 
to which section the species nevertheless belongs.