450 CHARACTERS OF -SEA-LIONS CHAP. 
Fam. 1. Otariidae.—The family Otariidae’* is no doubt the 
least modified of the aquatic Carnivora. It is rational, therefore, 
to commence the survey of the group with this family. They 
have preserved, as already noted, the independence of the hind- 
limbs; the external ear is present, though small; there is an 
obvious neck, and the nostrils are at the end of the snout, as in 
terrestrial creatures generally. The nails are small and rudi- 
mentary, save those upon the three middle digits of the foot. It 
is a singular fact that among the Otaries the angle of the lower 
jaw is “inflected as much as in any Marsupial.” The literature 
relating to this family is great, and it seems difficult to reconcile 
the very varying opinions as to how many genera ought to be 
admitted. Mr. Allen arranged the nine species which he allowed 
1 See especially Allen, North American Pinnipedes, 1880. 
