10 GILL, PRODEOME OF A 



STENORHYNCHIN^ (Gray.) 

 Maxillar zyo-omatic process with its lower and poste- 

 rior surface extended horizontally backwards, and its angle 

 continued far behind along the inner side of the malar. 

 Malar elongated, bow-shaped, and curved upward in front. , 

 Intermaxillaries narrow, not continued backward between 

 nasals and supramaxillaries. Nasal cavity expanded, with 

 the nasal bones widest toward the middle, and very long. 

 Incisors i . 



Synoj)sis of Genera. 



1. Molars I ; deeply lobed. Snoiit much longer than orbits, which are 

 moderate. 



* Molars (except first) unequally lobed, with a large recurved lobe ; 

 a small one in front, and two or three behind. Occipital condyles widely 

 diverging upward. Lobodon. 



** Molars trilobed. Occipital condyles nearly parallel. 



Stenorhtnchus. 



2. Molars j; "with a small conical tubercle on the hinder edge, and a 

 sharp edged ridge round the inner side of the base." Snout shorter than 

 the orbits, which are rather large. IiBptonyx 



3. Molars |; "compressed, with a central incurved lobe, and a small 

 lobe on each side of it." Snout shorter than the orbits, which are very 

 large. Ommatophoca. 



OTARIID^. 



The Otariidse are less attenuated than the Phocid£e 

 and have distinct external ears. The skull has " a post- 

 orbital process ; an alisphenoid canal ; mastoid process 

 strong and salient, standing aloof from the auditory bulla " 

 (Turner). Incisors 5.. Canines normally developed. Mo- 

 lars III or I I I . Anterior legs about as large as the 

 posterior, their toes decreasing in a curved line, and with- 

 out claws ; posterior feet, with the digits nearly cotermi- 

 nal, with long, membranacous longuiform flaps extending be- 

 yond their tips, and with the three median toes only clawed. 

 Scapula curved backward to the upper angle, but with its 

 spine or crest near the posterior margin.* 



* It may also be remarked that the nasals are as wide behind as in 

 front, extending toward their externo-posterior angles, and receive between 

 their produced portions a triangular extension of the frontal bones. 



