Phoca ursina, Cuvier, Oss. Foss. t. 219. f. 5.
Arctocephalus ursinus, F. Cuvier, Mém. Mus. vol. xi. p. 205, t. 15, no. 1. a, b, c (skull).
Otaria ursina, Nilsson.
Halarctus Delalandii, Gill, l. c. p. 7.
Otaria (Arctocephalus) pusilla, Peters, Monatsb. 1866, pp. 271 & 671.
Junior. Petit Phoque, Buffon, H. N. xiii. t. 53, = Phoca pusilla, Schreb.
Inhab. South Africa, Cape of Good Hope.
The two adult skulls in the British Museum differ greatly in the width of the hinder nasal opening, in the form of the hinder lower lateral processes of the occipital bone, in the form of the back of that bone, and in the shape of the condyles.
The skull from the Cape of Good Hope, in the Museum of the University of Edinburgh, was described and figured by Dr. Turner under the name of Arctocephalus schisthyperoës, in the ‘Journal of Anatomy and Physiology,’ vol. iii. p. 113. The name is changed to A. schistuperus by Dr. Günther in the ‘Zoological Record’ for 1868, p. 20. It is evidently the skull of a half-grown animal, with all its teeth developed, but with the sutures of the bones still apparent. It agrees in every respect with what I should expect to be the form and structure of the skull of Arctocephalus antarcticus from the Cape; but unfortunately the two skulls of that Sea-bear from the Cape which are in the British Museum are from old animals; and the specimen figured by Cuvier, Oss. Foss. v. 220, t. 18. f. 5, is also adult. It differs from the skulls of the two adult specimens of that species in the British Museum in the hinder nasal aperture being much extended forwards and gradually tapering to a point in front, which reaches to the transverse palato-maxillary suture. This peculiarity in the form of the palate, which Prof. Turner has not observed in any other seal-skull, seems to have induced him to regard it as a distinct species. From the examination I have made of the skulls of Seals in the Museum and other collections, I am induced to believe that it is an individual abnormality of Arctocephalus antarcticus. I have observed a similar malformation in the palates of two other species. I was myself misled by their structure, before I met with the other examples, to regard a skull with such a deformity as a distinct species.
At one time I thought that it might be a peculiarity of the young state, as it had up to that time only been observed in skulls of half-grown animals. It occurs in half-grown specimens of Euotaria nigrescens; but the skulls of the very young specimens of this Seal in the British Museum have the front edge of the hinder nasal opening truncated and slightly arched in form, with well-developed square palatine bones united by a central suture just as in the adult, but broader and straighter.