12 OTARIAD.S. 



in front ; the fifth and sixth grinders behind the front of the zygo- 

 matic arch. Flap of toes moderate. 



3. Phocarctos. Grinders large, lobed, the six upper with two notches 



on the hinder edge. Under-fur sparse. South America. 



4. Arctocephalus. Grinders thick ; crown conicaL Under-fur abundant. 



Tribe 4. Zalopikna. Grinders J-.f, large, thick, in a close continuous 

 series ; the fifth upper in front of the back edge of the zygomatic 

 arch. 



5. Zalophus. Grinders large and thick, in a close uniform series. 



Under-fur sparse. North Pacific. 



6. Neophoca. Grinders large, thick, all equal, in a continuous uniform 



series. Under-fur sparse. Flap of toes very short. Australia. 



Tribe 5. Eump:topiina. Grinders f . J- , more or less far apart ; the hinder 

 upper behind the hinder edge of the zygomatic arch, and separated 

 from the other grinders by a concave space. 



7. Eumctopias. Under-fur sparse. Flap of toes very short. West coast 



of North America. 



8. Arctophoca. Under-fur abundant. Flap of toes long. West coast 



of South America. 



Sect. I. Hie palate produced behind to a line even with the condyles. The 

 palatine surface of the mamillaries extending behind the teeth and with 

 its 2 J °sterior processes very long. It is deeply concave behind, and 

 becomes deeper as the animal increases in aye. The hinder nostril is 

 short, unth a truncated front edge. Flap of toes rather long. Sea-lions. 



Tribe I. OTARIINA. 



Otariina, Gray, Ann. § Mag. N. H. 1869, vol. iv. p. 269. 



1. OTARIA. 



Grinders 4. In the adult skulls the fourth upper grinder is under 

 the front edge of the orbit, and the sixth or last in a line with the 

 back edge of the zygomatic arch. The hinder edge of the palate is 

 rather in front, on the line of the condyles. The teeth in the 

 younger skull are more lobed than in the adult ; the upper grinders 

 are also differently disposed : the third upper grinder is under the 

 front edge of the orbit, and the fifth tooth is in a line with the back 

 edge of the zygomatic arch, and the last or sixth tooth is far behind 

 it (see skull, Cat. S. & W. p. 58, f. 18). This change is remarkable, 

 as the teeth of the young and the adult Zalophus Gittiespii are similar 

 in number and position. 



Otaria (subg. Otaria), Peters, Monatsb. 1866, p. 263. 



Otaria, Gray, Cat. Seals Sf Whales, p. 57 ; Ann. $ May. N. H. 1866, 



vol. xviii. p. 230 ; Gill, and Peters. 

 Platyrhynchus, F. Cuvier. 



