10 GILL, PRODKOME OF A 



STENORHYNCHIN^l (Gray.) 

 Maxillar zygoinatic 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 \. 



Synopsis of Genera. 



1. Molars | ; deeply lobed. Snout 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. LOBODOK. 



## Molars trilobed. Occipital condyles nearly parallel. 



STENORHTNCHUS. 



2. Molars 5-; "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. LEPTONYI 



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-EJ. 



The Otariidse are less attenuated than the Phocidas 

 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 -. Canines normally developed. Mo- 

 lars III or | | | . 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. 



