OTARIID.LE 593 
They always come on shore, however, for the purpose of bringing 
forth their young. They are generally marine, but they occasion- 
ally ascend large rivers, and some inhabit inland seas and lakes, as 
the Caspian and Baikal. Though not numerous in species, they 
are widely distributed over the world, but occur most abundantly 
on the coasts of lands situated in cold and temperate zones. The 
suborder is divisible into three well-marked families: the Ofuriidi, 
Fur-Seals or Sea-Bears, which form a transition from the Fissiped 
Carnivora to the Seals ; the Zrichechidw, containing the Walrus ; and 
the Phocide or typical Seals. 
The resemblances between the skull and other parts of the 
body of the Fur-Seals and the Ursoid true Carnivora is suggestive 
of some genetic relationship between the two groups, and Pro- 
fessor Mivart! expresses the opinion that the one group is the direct 
descendant of the other. The same writer goes on to suggest that 
if the Eared-Seals have been derived from Bear-like Carnivores this 
need not necessarily hold good with the true Seals, which may have 
had another, and possibly Lutrine, origin. The presence of an 
alisphenoid canal in Ursus and the Ofariide, and its absence in Lutru 
and the Phocidw, together with other osteological features, are cited 
in support of this view; but although these resemblances and 
differences are certainly remarkable, yet much more evidence is 
required before the hypothesis can be accepted as even a probable 
one. It must, moreover, be borne in mind that the true Bears are 
a very modern group; and there is a possibility that the Pinnipeds 
may prove to have been independently derived from the extinct 
Carnivora noticed below under the name of Creodonta. 
Family OTARUD. 
When on land the hind feet are turned forwards under the body, 
and aid in supporting and moving the trunk as in ordinary mammals. 
A small external ear. Testes suspended in a distinct external 
scrotum. Skull with postorbital processes, and an alisphenoid canal. 
Angle of mandible inflected. Palms and soles of feet naked. 
Otaria.2—Dentition: i 3, ¢ 1, p 4, m cele total 34 or 36. 
First and second upper incisors small, with the summits of the 
crowns divided by a deep transverse groove into an anterior 
and a posterior cusp of nearly equal height; the third large and 
canine-like. Canines large, conical, pointed, recurved. Molars and 
premolars usually 4, of which the second, third, and fourth are 
preceded by milk-teeth shed a few days after birth: sometimes (as 
in Fig. 271) a sixth upper molar (occasionally developed on one 
l Proce. Zool. Sov. 1885, p. 497. 
> Péron, Mouage aux Terres Australes, vol. ii. y. 37 note (1816). 
38 
