PRODROME 
OF A 
Monograph of the Pinnipedes, 
BY 
THEODORE G-ILIO. 
From the 
PROCEEDINGS OP THE ESSEX INSTITUTE, 
Vol. V. IV o. T. 
SALEM, MASS. 
t’u'blisUed April 7, 1800. PRODROME 
OF A 
Monograph of the Pinnipedes, 
1«Y 
THEODOBE GILL. 
tlio 
PROCEEDINGS OF THE ESSEX INSTITUTE, 
Vol. V. IVo. I. 
SALEM, MASS. 
I’ublinhfU .A-pril 7, 18011. I. Prodrome of a Monograph of the Pinnipedes. 
Theodore Gill. 
(Communicated October 16, 1865.) 
The Seals of America have been hitherto little known, 
and in the general works on the mammals of the northern 
continent, they, like the bats and cetaceans, have been 
omitted. 
With a view to the elucidation of the species, and at 
the suggestion of Professor Baird, I have been induced to 
undertake the examination of the collection of specimens 
in skin, and the skulls and skeletons possessed by the 
Smithsonian Institution and the Academy of Natural Sci- 
ences of Philadelphia. To Mr. F. W. Putnam, Superin- 
tendent of the Museum of the Essex Institute, and Professor 
W yman, I am much indebted for the kindness manifested in 
transmitting to me the specimens they possessed, and the 
opportunity thus afforded for comparison and study of 
more extensive material. The results of the examination 
of these specimens are now given, in so far as the classifi- 
cation and relations of the primary groups and genera are 
concerned, while I am obliged to defer until a more conven- 
ient season the more elaborate exposition of the views I 
have been compelled to embrace, as well as the discussion 
of the limits and nomenclature of the species. 
Passing over the changes which the seal exhibits in its 
progress to adolescence, I would advert to the peculiarities 
in the geographical distribution of the several groups in 
connection with their systematic relations. 
The three primary groups which may be elevated to 
the rank of families, in the first place, are very differently 
distributed. 4 
GILL, PRODROME OF A 
The Phocide are cosmopolitan, and representatives are 
found in the tropical seas, as well as in the waters of the 
extremest north and south, the Indian Ocean being the 
only large body of water in which no species are found. 
While such, however, is the expression of the general dis- 
tribution of the family, its minor groups are much more 
narrowly restricted. The three subfamilies, into which the 
family is divided, are each distinguished by peculiarities 
in limitation. The Phocine are almost confined to the 
polar and northern temperate seas, representatives of a 
single genus extending southwards to or beyond the tropic 
of Cancer * while the Stenorhynchine, after the exclusion 
of Monachus, whose affinities are essentially with the Pho- 
cina, are confined as strictly to the opposite hemisphere. 
The Cystophorine, on the other hand, are represented at 
both extremes; the species of one genus, Cystophora, inhabit- 
ing the Arctic seas, whence it descends into the more 
northern temperate Atlantic on both sides; while Macro- 
rhinus is represented by a species found in the Antarctic 
seas, whence it advances to the Patagonian shores and the 
Pacific coast of temperate South America, the southern 
Australian seas and the Cape of Good Hope, and on the 
other side of the Equator, but still in the Pacific ocean, 
is replaced by a species peculiar to the warmer waters that 
bound the North American continent on the west. The 
exact limits of these species require, however, yet to be as- 
certained. The Rosmaride are entirely confined to the 
northern Polar seas. The Otariide have their metropolis 
in the Pacific ocean, and are represented by species along 
* The “ Halichcenis antarctievs” of Peale, very erroneously identified 
with Lobodon carcinophoyu by Dr. J. E. Gray, is a typical species of Phocat 
but appears to be identical with a species occurring along the California 
and Oregonian coasts, and, consequently there must be some error as to 
its assigned habitat in the antarctic seas. I am happy to add that Mr. Peale 
himself now doubts the correctness of the labels on the faith of which he 
gave its habitat, and as a change of name is desirable, I would propose that 
of P. Pealii. 
The relations of the Jamaican seal, rejoicing in the two names, Phocd 
tropicalis Gray and ? ! Wilkianus Gosse (1851), are very uncertain. 
Mr. Gosse obtained a single skin. The exact origin of the Cystophora antil- 
larum was not mentioned in the original description, and its West Indian 
habitat requires confirmation. MONOGRAPH OF THE PINNIPEDES. 
5 
the entire western coast of America, except the tropical 
regions, while on the eastern they ascend towards Brazil. 
They are likewise abundant along the Australian coasts. 
In conclusion, it may be added, as Peron and Dr. Gray 
have before insisted, that the species of the entire group 
are restricted within as distinct geographical limits as are 
any other mammals, and as are especially the marine fishes. 
Without further preface, I submit the following classifi- 
cation to the judgement of naturalists : 
FAMILY I. PHOCIDiE Brookes, Gervais. 
SUBFAMILY I. PHOCINiE (Gray), Gill. 
Genus 1. Phoca Linnaeus. 
Syn. Callocephalus F. Cuvier, 1824, Gray, 1844. 
llalicyon Gray, 1864. 
Type. Phoca vitulina Linnccus.* 
Genus 2. Pagomys Gray, 1864. 
Type. Phoca f«tida Muller. 
Genus 3. Pagophilus Gray, 1844. 
Type. Phoca grcenlandica Muller. 
Genus 4. Erignathus Gill, 1865. 
Syn. Phoca Gray, 1844. 
Type. Phoca iiarbata Fabricius. 
Genus 5. Halichggrus Nilsson, 1820. 
Type. Phoca grypus Fabricius. 
* In the Syst. Nat. 10th cd., 1758, the first id which the binomial sys- 
tem was introduced, four species were included by Linnaeus in the genus 
Phoca; 1, P. ursina,=Arctocephalus ursinus; 2, P. leonina,—Mac- 
uokiiinus lkoninus; 3, P. rosmarus,=Rosmarus obesijs; 4, P. vitulina. 
The name I’iioca must be retained for one of these, and as the third, second 
and first species were successively elevated to the rank of generic types, and 
the genus was thus by elimination restricted to the fourth species, for that 
and its allies, the generic name must necessarily be reserved. 6 
GILL, PRODROME OP A 
Genus 6. Monachus Fleming, 1822, Gray, 1850. 
Syn. Pelagios F. Cuvier, 1824, Gray, 1844. 
Heliophoca Gray, 1854. 
Type. Phoca monachus Hermann. 
SUBFAMILY II. CYSTOPHORINJE Gray. 
Genus 7. Cystophora (Nilsson, 1820), Gray, 1844. 
Syn. Stemmatopus F. Cuvier, 1824. 
Type. Phoca cristata Erxleben. 
Genus 8. Macrorhinus F. Cuvier, 1824. 
Syn. Mirounga Gray, 1827. 
Macrorhyna Gray, 1827. 
Morunga Gray, 1844. 
Type. Phoca leonina Linnceus, 1758. 
SUBFAMILY III. STENORHYNCHIIY® (Gray), Gill, 
Genus 9. Lobodon Gray, 1844. 
Type. Phoca carcinophaga Hombrcm and Jacquinot:* 
Genus 10. Stenorhynchus F. Cuvier, 1824. 
Type. Phoca leptonyx Blainville. 
Genus 11. Leptonyx Gray, 1836. 
Type. Stenorhynchus Weddellii Lesson. 
Genus 12. Ommatophoca Gray, 1844. 
Type. Ommatophoca Rossii Gray. 
* The Halichcerus antarcticus Peale, referred by subsequent authors to 
Lobodon carcinophaga, has no affinity with it. The species is a typical Phoca, 
closely allied to P. vitulina, and was correctly described by Mr. Peale. The 
type specimens of skins and skull are in the Smithsonian Museum. MONOGRAPH OF THE PINNIPEDES. 
7 
FAMILY II. OTARIIDZE Brookes, Gervais. 
Genus 1. Otaria Peron, 1816. 
Syn. Platyrhynchus F. Cuvier, 1824. 
Otoes Fischer. 
Plalyrhinus Lesson. 
Otiphoca Blainville. 
Type. Phoca jubata Schreber. 
Genus 2. Arctocephalus F. Cuvier,* 1824. 
Syn. Callorhinus Gray, 1864. 
Type. Phoca ursina Linnaeus. 
Genus 3. Eumetopias Gill, 1865. 
Type. Otaria californiana Lesson., = Arctocephalus 
monteriensis Gray, t 
Genus 4. Zalophus Gill, 1865. 
Type. Otaria Gilliebfii Macbain. 
Genus 5. Halarctus Gill, 1865. 
Type. Arctocephalus Delalandii Gray. 
FAMILY HI. ROSMARIDiE Gill. 
Syn. Trichechidce Brookes, Gervais. 
Genus 1. Rosmarus Scopoli, 1777. 
Syn. Odobcenus (Brisson), Illiger. 
Trichechus Auct. recent.t 
Type. Trichechus rosmarus Linncrus. 
* Arctocephalus F. Cuv. was especially established for a species con- 
sidered identical with Phoca ursina Linn, and as no other species was men- 
tioned, and, as the identification appears correct, the name must be retained 
for that species. 
t Is not A. monteriensis Gray identical with Otaria Stelleri Mull. Arc. fur 
Nat. 1841, I. 330? 
I Trichechus was originally based solely on the Manati (T. Manatus) 
by Linnaeus, Syst. Nat. 10 ed. 1758, I. 34. It must therefore be retained for 
that animal. 8 
GILL, PRODROME OF A 
These families, subfamilies and genera may be dis- 
tinguished as follows: 
PHOCID^l. 
The Pliocidse are the most elongated in form, and have 
the external ears obsolescent. The skull has the postorbi- 
tal processes null or obsolete; “ no alisphenoid canal; the 
mastoid processes swollen and seeming to form part of the 
auditory bulla.”* Incisors;,- ~ ; Canine teeth nor- 
mally developed. Molars f | ~ ; rarely -5 | £ (in Ommato- 
phoca). Anterior and posterior feet provided with claws; the 
anterior legs smaller than the posterior, with the digits of 
the feet successively abbreviated ; the • posterior flippers 
emarginated; the third and fourth digits being shortest. 
Scapula in the Phocinas expanded upward and backward 
toward the postero-superior angle, the surface behind the 
spine being enlarged. 
In the family, thus limited, three subordinate types are 
embraced, which may be distinguished as subfamilies. These 
are especially differentiated by modifications of the skull 
and feet. In the discrimination of the genera, many char- 
acters have been omitted, as unadvisable to introduce in a 
mere synopsis. Most of the characters selected for the 
distinction of the subfamilies have been hitherto overlooked. 
Their universality and their coincidence have been verified 
by reference to all the known types, t 
PHOCINJE (Gray.) 
Maxillar zygomatic process with the posterior surface 
sub vertical, or very oblique. Malar oblong-rhomboid, 
emarginated above and below. Intermaxillaries narrow, 
prolonged, and wedged behind between the supramaxillarics 
and nasals. Nasal bones narrow, diminishing in width 
backwards. Incisors £; exceptionally \. 
* Turner. Proc. Zool. Soc. London, 1848, p. 88. The constancy of 
the characters used by Turner has been verified by myself, by reference to 
all the types. 
t The genera Momcktm, Lobodon, L?ptonyx and Ommaiophoca arc au- 
topically unknown to me, but the published illustrations demonstrate the 
applicability of the characters in question. MONOGRAPH OF THE PINNIPEDES. 
9 
Synopsis of genera. 
♦Incisors curved, conic, small. Bony palate produced forward between 
lateral extensions of the maxillaries, quite or nearly to aline with the poste- 
rior molars. 
t Skull declining at nasal region; anterior nares moderate; molars, ex- 
cept first, with two roots. * 
} Maxillar zygomatic processes arising from edge of jaw, with the sur- 
face very oblique and the suborbital foramen inferior. Jaws rectilinear. 
а. Lower jaw with its branches flattened within. Teeth complex. 
Phoca. 
б. Lower jaw with its branches inflected inwards. Teeth simple. 
1. Palate emarginated behind ; very deeply incised at the septum 
narium. Pagomys. 
2. Palate entire and transverse behind; septum narium entire and 
continued to the posterior edge of palate. Pagophilus. 
It Maxillar zygomatic process high up, with the surface little oblique, 
and the suborbital foramen anterior. Jaws curved outward. Palate very 
broad, emarginated. Base of skull with posterior lateral vacuities obsoles- 
cent. Erignathus. 
tt Skull increasing in height forward. Anterior nares very large ; mo- 
lars single rooted. Halichocrus.* 
** Incisors j; enlarged, transversely notched behind their edges. Bony 
palate emarginated behind and with a notch at suture; the bones not pro. 
duced as far forward as the inner margin of orbit. Monachus.I 
CYSTOPHORIN.® Gray. 
Maxillar zygomatic process with the posterior surface 
subvertical, or very oblique. Malar bone elongate-rhom- 
boid, einarginatcd above and below. Intermaxillaries 
terminating far from nasals. Nasal bones narrow and rath- 
er short. Incisors . 
Synopsis of genera. 
* Bony palate nearly square, subtruncated behind. Adult males with 
a large dilatable compressed hood extending from the nose to occiput. 
Cystophora. 
** Bony palate very short, emarginated by a deep sinus behind. Adult 
males with an extensible tubular proboscis. Macrorhinus. 
•Tlie affinity of Halieharus to Rosmarua (Trichcchus Auct.) is not evident, 
tManarhus, approximated by all preceding naturalists to the Stenorhynchi, appears 
to te tar more nearly related to the Phocec. 
COMMUNICATIONS ESSEX INST., VOL. V. 2. MaBCH, 1866. 10 
GILL, PRODROME OF A 
STENORHYNCHIN51 (Gray.) 
Maxillar zygomatic process with its lower and poste- 
rior surface extended horizontally backwards, and its angle 
continued far behind along the inner side of the malar. 
Malar elongated, bow-shaped, and curved upward in front. 
Intermaxillarics narrow, not continued backward between 
nasals and supramaxillaries. Nasal cavity expanded, with 
the nasal bones widest toward the middle, and very long. 
Incisors \ . 
Synopsis of Genera. 
1. Molars §; deeply lobed. Snout much longer than orbits, which arc 
moderate. 
* Molars (except first) unequally lobed, with a large recurved lobe ; 
a small one in front, and two or three behind. Occipital condyles widely 
diverging upward. Lobodon. 
** Molars trilobed. Occipital condyles nearly parallel. 
Stenorhynchus. 
2. Molars “with a small conical tubercle on the hinder edge, and a 
sharp edged ridge round the inner side of the base.” Snout shorter than 
the orbits, which are rather large. Leptonyx. 
3. Molars “ compressed, with a central incurved lobe, and a small 
lobe on each side of it.” Snout shorter than the orbits, which are very 
large. Ommatophoca. 
OTARIIDiE. 
The Otariidae are less attenuated than the Phocidae 
and have distinct external ears. The skull has “ a post- 
orbital process; an alisphenoid canal; mastoid process 
strong and salient, standing aloof from the auditory bulla ” 
(Turner). Incisors |. Canines normally developed. Mo- 
lars | \ or - | |. Anterior legs about as large as the 
posterior, their toes decreasing in a curved line, and with- 
out claws ; posterior feet, with the digits nearly cotermi- 
nal, with long, membranacous longuiform flaps extending be- 
yond their tips, and with the three median toes only clawed. 
Scapula curved backward to the upper angle, but with its 
spine or crest near the posterior margin.* 
* It may also be remarked that the nasals are as wide behind as in 
front, extending toward their externo-posterior angles, and receive between 
their produced portions a triangular extension of the frontal hones. MONOGRAPH OF THE PINNIPEDES. 
11 
This family, especially developed in the Pacific, is rep- 
resented by several genera, which may be distinguished as 
follows: — 
I. Palatal surface of maxillaries extending behind the teeth, and with 
its posterior processes very long. Bony palate extending nearly to tho 
pterygoid processes and truncated or convex behind. Otari a.* 
II. Palatal surface of maxillaries at middle not extending beyond the 
grinders, and with moderate lateral extensions. Bony palate very deeply 
emarginated. 
a. Face high, boldly decurved and shorter than orbit. Molars £-> 
approximated, compressed, conic. 
ARCTOCEPHALUS.t 
b. Face produced, longer than orbit. 
1. Molars j-; last upper far behind the inner margin of orbit. 
Posterior nares very high and narrow. Bony palate with a very narrow 
cmargination, notched at suture. Forehead very thick and tumid, with a 
triangular flattened area. Postorbital processes quadrate. Eumetopias. 
2. Molars approximated ; last under zygomatic process; poste- 
rior nares wider than high behind. Bony palate w ith a continuous concave 
cmargination behind. Forehead, depressed, with triangular postorbital 
processes. Occipital crest very high. Zalopiics. 
3. Molars ; lower more or less trilobate; last upper behind in. 
ner margin of zygomatic process. IIalarctus. 
ROSMARIMJ. 
The Walrusses have a very robust body, and no external 
ears. The skull provided with “ no postorbital processes; 
a distinct alisphenoid canal; mastoid process strong and 
salient ; its surface continuous with the auditory bulla ” 
(Turner). Incisors deciduous; the external, on each side 
being alone retained in the gums. Canines extraordinarily 
* Otaria is said by Dr. Gray, in liis last enumeration of the family, to have “ the 
palate very concave, d>curved deeper with age, l(c." I cannot understand tuch a state- 
ment with regard to the bony palate ot Otaria leonina, and consequently describe 
the appearance of the bones as they appear to me. 
t As I have known it to be suggested that the A. monteriensis and A. Gilliespii 
may be identical, it may be proper to state that the first is not found in the South, 
where th ■ other species dwell, although the second may inhabit the same regions in 
the North. The differences between the three species are so great, that it may be al- 
most a matter of surprise that they should not have been generically separated be- 
fore. I have examined the complete skeleton ar.d three skulls of adults of A. 
monteriensis ; the skull of a very old male of A. Gilliespii ; and skulls of live young 
specimens of A. ursinus, besides part of the skeleton. 12 
GILL, PRODROME OP A 
developed as tusks. Molars in young ~ ; the fifth and 
fourth caducous. Anterior feet about as large as posterior, 
with the toes decreasing in a curved line, destitute of 
claws ; the posterior feet with the five digits, scarcely in- 
creasing toward inner, all provided with claws. Scapula 
with the hinder margin nearly straight, and the spine a 
short distance from, and somewhat parallel with it. 
* One genus. 
Rosmarus. 
APPENDIX. 
For the benefit of American naturalists, a list of the 
species of Seals inhabiting both coasts of North America, 
is here given. I may add that I have seen more or less 
numerous specimens of every species enumerated. 
Pinnipedes of Eastern North America. 
PHOCIDJ3. 
PHOCINAl. 
1. Phoca vitulina Linnaeus. Greenland to New York. 
2. Pagomys foetidus Gray. Greenland to Labrador.* 
3. Pagophilus grcelandicus Gray. Greenland to 
Gulf of St. Lawrence. 
4. Erignathus harbatus Gill. Greenland to Gulf of 
St. Lawrence. 
5. Halichoerus grypus Nilsson.f Sable Island. 
* The Phoca fcetidci and P. hispida appear to simply represent condi- 
tions of a single species exhibiting a remarkable variation in dentition. 
An examination of numerous specimens, differing in the number of the 
cusps, forbids my considering such variations as constant and indicative of 
specific value. They surely cannot be generically separated as Dr. Gray has 
done. 
t The American form of Halichoerus differs somewhat from any of the 
three forms signalized by Hornschuch, but the names of that gentleman 
have not been regarded by others as the expression of valid species, and do 
not really appear to merit recognition. I have therefore, provisionally at 
least, identified the American type with the European, combining all the 
known forms of the genus under one specific name. MONOGRAPH OP THE PINNIPEDES. 
13 
CYSTOPHORIN^E. 
C. Cystophora crist at a Nilsson. Greenland to 
New York. 
ROSMARIDA3. 
7. Rosmarns obcsus Gill ex Illiger. Greenland to Lab- 
rador; formerly to Nova Scotia. 
Pinnipedes of California, Oregon, fyc. 
PIIOCID^E. 
PHOCIN^E. 
1. Phoca Richardi Gill ex Gray. British Columbia, 
(southwards, to California ?) 
2. Phoca Pcalii Gill. California and Oregon. 
CYSTOPHORIN.E. 
3. Macrorhinus angustirostris Gill.* California. 
OTARIIDyE. 
4. Arctoccphalus ursinus F. Cuvier. Behring’s Straits 
to Washington Territory. 
5. Eumelopias californianus Gill.f California. 
6. Zalophus Gilliespii Gill ex Macbain. South 
California. 
ROSMARlDiE. 
7. Rosmarus obesus Gill ex Illiger. Arctic Seas. 
* Afacrorhinus aujtulirottris is distinguished by its narrow snout, and 
the form of the palatine bones, &c. It will be described in the l’roc. Chicago 
Acad. Nat. Sc. 
tTlie Eumetopias call for nian'is is identical with the Otaria montcriensis of 
Gray, and possibly also with Otaria Stelleri Muller.