418 Zoological Society. 



their continuity with the borders of the epiglottis, proceeds to point 

 out the differences presented by that of the Cats, and briefly observes, 

 *' Le Mangouste et la Civette ont la glotte comme les Chats." He 

 then describes a third variety of structure presented by the Bears, 

 and mentions differences in the Racoon, the Badger, the Marten, the 

 Otter, and the Coati, consisting merely of variations presented by 

 the chordae vocales, and in some the superaddition of sinuses, doubt- 

 less only adaptive modifications to the different kinds of voice. 



In the foregoing observations nothing has been remarked with 

 reference to the Seals, nor indeed is it absolutely necessary ; for the 

 limits of a group, so distinctly marked and peculiarly modified, are 

 never at all likely to be mistaken ; but as this singular family is 

 truly and essentially a portion of the order whose arrangement it is 

 here my endeavour to elucidate, a few observations upon them may 

 seem a little called for. Naturalists have long been accustomed 

 to separate from the rest those which are distinguished externally 

 by the presence of the small external ear, and the long riband-like 

 processes of skin projecting from the toes of the hind-feet. These 

 genera, Otaria and Ar otocephalus, are also in their cranial characters 

 the most distinctly separable from the rest, through which, with the 

 exception of the Walrus, a great uniformity prevails, so that a men- 

 tion of the characters in which the common Seal differs from those 

 having external ears may perhaps suffice. Here there is no trace of 

 a postorbital process, nor of an ali-sphenoid canal ; the mastoid can 

 scarcely be said to constitute a process ; it is swollen, and appears to 

 form a portion of the auditory bulla, more or less connected with the 

 tympanic portion, from which it is separated by a depressed groove 

 running from the stylo-mastoid foramen backwards and a little in- 

 wards. The paroccipital process is never large in any of the family, 

 but it is always distinctly developed, and salient backwards. The 

 Arctocephaline group are distinguished at once by their having a 

 distinct postorbital process and an ali-sphenoid canal ; the mastoid 

 projects as a strong process, and seems, as it were, to stand aloof 

 from the auditory bulla, which is small and rounded. The carotid 

 canal has precisely the same course as that pointed out in the Bears 

 and Dogs, while in the common Seal it enters rather more forward, 

 and does not show itself again externally. The Arctocephalina have 

 the orbito- sphenoids much compressed together anteriorly to the 

 optic foramina, which almost appear to have coalesced into one : they 

 are also remarkable for the strong development of a process on the 

 anterior part of the rim of the orbit ; this however will not well serve 

 as a character, since it is apparent, though in a much less degree, in 

 some of the larger species of the ordinary type, as the Stenoryhnchus 

 leptonyx. The Walrus is a peculiar form which I should deem it 

 advisable to constitute a distinct subfamily, since I cannot concur 

 with Mr. Gray in associating with it the Halichcerus grj/pkus, whose 

 skull presents all the characters of the true Seals, the elevation in 

 the nasal portion having no relation whatever with the immensely 

 swollen upper jaw of the Walrus, which is necessitated by the enor- 

 mous size of the canine teeth : in this animal there is no postorbital 



