16. ABCTOCEPHALUS. 



47 



under-fur. This proves that the Seak from the different parts of the 

 west coast of America are distinct from each other, each specimen 

 having a specific geographical range. 



16. AECTOCEPHALUS. 



Muzzle rather tapering in front. Cutting-teeth |-, upper nearly 

 square. Grinders ~. Palate of the skaR rather narrower behind 

 than in front, short, scarcely reaching to the middle of the zygo- 

 matic arch. Lower jaw-bone narrow, rounded below, without any 

 angle behind. 



The face and skull rather elcjngate ; the forehead flattened, and 

 nearly horizontal from the nasal bone to the vertex ; the palaterather 

 concave, contracted behind, short, not reaching beyond the middle of 

 the zygomatic arch ; the nose-aperture large, high ; the lower jaws 

 moderate, with a crest-Uke ridge behind, beneath, just in front of the 

 condyle. 



The crest-like process on the hinder part of the under edge of the 

 lower jaw differs somewhat in shape and development in the different 

 species ; but it nowhere resembles the flat expanded disk found in a 

 similar situation in the lower jaw of the preceding genus. 



Nose simple, with a rather large callous muffle above and between 

 the nostrils. Whiskers cylindrical, thick, round, tapering, not waved ; 

 hinder ones largest. Ears with a subcylindrical, distinct, external 

 conch. 



Fig. 17. 





wt'^v . 



Arctocephalus Hookeri. Skull, palate, and grinder. 



The fore feet elongate ; the palms bald, longitudinally grooved ; 

 claws five, very small, rudimentary, scarcely visible. Hind limbs 

 rather produced ; the legs free. The hind feet elongated ; the soles 

 bald, longitudinally grooved ; the toes subequal, short, webbed, and 

 each furnished with a long membranaceous expansion, the web and 

 the membranaceous expansion bald. 



