428 Proceedings of the 



amongst those of the two genera Arctocephalus and Otaria ; 

 nor are they included in Dr Gray's description of the sub- 

 family Arctocephalina. These are, the number of molar 

 teeth on each side of each jaw, and the remarkable longitu- 

 dinal sagitto-coronal crest, which could not have been over- 

 looked by any zoologist. The dental formula of Arctocepha- 

 lina by Dr Gray is — cutting teeth six above, four below, upper 

 often bifid ; grinders, six on each side of eaeh jaw, equal to 

 twenty-four. In this skull the number of molars are five on 

 each side of each jaw, and there is no trace of a nidus for 

 another molar behind. I owe the possession of the skull to 

 my friend Dr John Gillespie of Leith, who obtained it from 

 a sailor just returned from California. The seaman stated, 

 that he had found it at the mouth of the Red River, which we 

 infer to be the Rio Colorado at the head of the gulf. 



In the " History of British Quadrupeds," the author re- 

 marks, " There is not, I believe, a single group among the 

 whole of the mammiferous class which is at present so indis- 

 tinctly known, and of which the species are so much con- 

 founded, as the seals." This statement, added to the remark 

 of Peron, " that there really exist more than twenty seals 

 which go under the name of sea-bear," will be a sufficient ex- 

 cuse for giving this description of the skull to the Royal 

 Physical Society. Assuming this to be the skull of the Otary 

 of Stellar, which has already received the synonym of Otaria 

 Californiana, it possesses very great interest as one of the 

 "desiderata" requested by Dr Gray in 1850 for the British 

 Museum. And no skull of that species is mentioned in the 

 British Museum catalogue as existing in any of the Conti- 

 nental museums of Europe. Therefore, until this is ascer- 

 tained, it would be premature to institute a new genus founded 

 upon the difference in dentition, and the remarkable longitu- 

 dinal sagitto-coronal crest peculiar to this cranium. Trusting, 

 rather, that it may eventually prove to belong to one of the 

 twenty undescribed so-called sea-bears of Peron, it may, in 

 the meanwhile, very appropriately receive the provisional 

 name of Otaria Gillespii. 



