and Sea-Lions in the British Museum. 231 



the orbit, and the last in front of the back edge of the zygomatic arch. 

 Zalophina. 



In the younger skull the grinders are placed rather further 

 back, the hinder part of the upper grinder being behind the 

 back edge of the zygomatic arch. The grinders all single- 

 rooted^ as the last or sixth grinder in each jaw, which is generally 

 two-rooted, is absent. The face of the skull is considerably 

 produced, and the forehead is flat. 



2. Zalophus, Gill, Peters. 

 Arctocephaltis § b **, Gray, Cat. Seals & Whales, p. 56. 

 Palate concave, narrow in front, wider at the line of the last 

 grinder, and then contracted behind. The hinder nares nar- 

 row, elongate, twice as long as wide, acutely arched in front, 

 front edge in a line with the front edge of the orbital process 

 of the malar bone. 



Zalophus Gilliespii, Gill. • 



Otaria Gilliespii, Macbain & Peters. 



Arctocephalus Gilliespii, Gray, P. Z. S. 1859, t, 70 (skull). 



Hab. California. Brit. Mus. 



3. Neophoca. 



Arctocephalus § b ***, Gray, Cat. Seals & Whales, p. 57. 

 Otaria, § Zalophus, part., Peters. 



Palate concave, broad, as broad before as at the hinder part 

 of the tooth-line, then rather suddenly contracted. The hinder 

 nares broad, rather longer than broad, with the front edge 

 broadly arched, which is further back than the front edge of the 

 orbital process of the zygomatic arch, or malar bone, which is 

 thick and flat. 



Neophoca lohatus, Australian Hair-Seal. 



Arctocephalus lobatus, Gray, Spic. Zool. 1828, t. 4. f. 2 (teeth) ; Zool. E. & 

 T. Mamm. 1. 1 6, 17. f. 3-5 (skull) ; Gray, Gould, Mamm. Austr. iii. t. 49 ; 

 Peters. 



Otaria australis, Quoy & Gaim. Astrol. t. 14, 15. f. 3, 4 (skull). . 



Otaria Stelleri, Schlegel, Abbild. t. 22. f. 1-4. 



Arctocephalus australis. Gray, Cat. Seals & Whales, p. 67. 



The upper grinders all single- rooted, the root of the two last 

 (the fourth and fifth) being rather compressed, with an obscure 

 central longitudinal groove on the inner side; the two front 

 grinders of the lower jaw with oblong, the three last with 

 compressed roots, and the fourth and fifth with a slight longi- 

 tudinal central groove on the sides. 



In the younger skulls the roots of the grinders are more ob- 

 long, less compressed, and do not show the lateral grooves, as far 

 as the teeth can be seen without being drawn from the sockets. 



