38 BULLETIN OF THE 



greatly subdivide each of these groups. Olaria is now restricted to a 

 single species; while the original Otaria (=Otariadce), as defined by 

 IYron, has been separated into ten groups to which generic rank has 

 been accorded ; none of them containing more than a single species. 



The first division of the Otarice was made by F. Cuvier* in 1825, 

 who separated them into two genera, Platyrhynchus and At 'otocephalus, 

 with the 0. jubata of recent systcmatists as the type of the former, and 

 Arctocephulus Delalandii ' (antarctic us) as the type of the latter. Dr. 

 Gray,t in 185 9, separated generically the Northern fur seal from Arc- 

 tocephalus, under the name of Callorkinus. 



The next subdivision of the group was made by Dr. Gill, + in 18GG, 

 who in his " Prodrome of a Monograph of the Pinnipedes," separated 

 them into five genera. § These appear to be natural groups, of true 

 generic rank, and properly restricted ; and, after a careful examination 

 of the subject, and specimens of four of these five types, they appear 

 to me to include all the natural genera of the family. As has been 

 previously pointed out by Gray and Peters, || Dr. Gill, as he himself 

 now freely admits, wrongly retained the name Arctocephulus for Gray's 

 genus Callorkinus, and consequently substituted Ilalarctus for what had 

 previously been regarded as Arctocephalus. Two of these genera 

 (Eumetopias and Callorkinus) iuclude but a single known species each ; 

 Otaria has possibly two, Zalophus two, and Arctocephalus, according to 

 the views of different writers, three or four. 



Professor Peters, ^[ in 18GG, divided Olaria into seven sections or 

 subgenera, he adding two (Phocarctos, type Otaria Hooheri, and Arcto- 

 pkoca, type Otaria Philippii, a nominal species-, = Arctocephalus falh- 

 landicus) to the number of divisions recognized by Gill. The principal 

 character on which the latter (Arctophoca) was first founded proved to 

 be an invalid one,** yet it was subsequently transferred by Peters, with 

 a slight modification of its diagnosis, to the Arctocephalus falhlandicus. 



* Mem. dii Mus., Vol. XI, p. 205. f Proc. Lond. ZooL Soc, 1859, p. 359. 



| Proc. Essex Institute, Vol. V, p. 7. 



§ Otaria, type Phoca jubata Schreber; Arctocephalus, type Phnca ursina Linne; Eume- 

 topias, type Otaria calijorniana Lesson, ■■ Arctocephalus monteriensis Gray; Zalophus, 

 type Otaria GiUespii McBain; Halarctus, type Arctocephalus Delalandi Gray. 



|| See above, p. 7 of the " Resume." \\ Monatsb. Akad. Berlin, 1866, pp. 261, 665. 



** The number of molars of A. Philippii was supposed to be | ~| instead of f — £> 

 u- in the other fur seals, but the skull figured and described by Peters as that of this 

 species bad evidently lost the fifth (last but one) pair of molars, as shown by his figure 

 of the skull. 1'eters himself afterwards referred his A. Philippii to the A. falhlandicus. 



