KEY TO LAND MAMMALS OF NORTHEASTERN NORTH AMERICA 121 



Family Phocidae Earless seals 

 Hind feet directed permanently 'backward; no etxemalears; no tusks. 

 (P h 6 c i d a e ; genus P h o c a ) 



The family Phocidae contains a dozen or more genera distributed 

 on practically all sea coasts. Four occur in North America, all of which 

 are represented within our limits. 



GENERA OF PHOCIDAE 



Teeth 30; suout of male developed into a conspicuous "hood" 



(subfamily C ystophorinae) Cystophora 



Teeth 34; snout not specially developed (subfamily Phocinae) 



Braincase forming less than one third of length of skull Halichoerus 



Braincase forming nearly one half of length of skull 



Cheek teeth large and strong ; forehead high, arched Phoca 



Cheek teeth small and weak ; forehead low, flat Erignathus 



Genus Cystophora Nilsson 

 1820 Cystophora Nilsson, Skand. fauna. 1 : 382. Type Cystophora 

 borealis Nil88on=P hoca cristata Erxleben. 

 Teeth 30 {only tivo front teeth in lower jaw) ; muzzle elongated, that of male 

 capable of inflation. (C y s 1 6ph or a; Gk., bladder-bearer) 



The genus Cystophora is peculiar to the coasts and islands of 

 the North Atlantic. Only one species is known. 



Cystophora cristata (Erxleben) Hooded seal 



1777 [Phoca] cristata Erxleben, Syst. regn. anim. 1 : 590. (Greenland) 



1837 C y s t oph or a cristata Nilsson, Kongl. Vet. akad. Handl. Stock- 

 holm. 



1880 Cystophora cristata Allen, History of North American pinnipeds, 

 p. 724. 



1884 Cystophora cristata Merriam, Science. 5 Dec. 1884. 4:514. 

 Bluish black, lighter on sides and belly; back thickly sprinkled with irregular 



whitish spots. Total length 2450 (7ft) to 2800 (8 ft). (cristata; Lat., 



crested) 



The hooded seal occurs on the northern coasts of western Europe 

 and eastern North America. In the latter country its southward range 

 extends about to Nova Scotia, though stragglers have been taken as far 

 south as Long Island. 



Genus Halichoerus Nilsson 

 1820 Halichoerus Nilsson, Faun. Skand. 1 : 377. Type 1 1 a 1 i c h o o r ii s 

 g r i 8 6 u s Nilsson=P hoca grypus Fabricius. 



Teeth 34 (four front teeth in lower Jaw); braiucaso very small, fouuinj; K>ss 

 than cue third length of skull. (H a li c h o «'• r u a ; Gk., sea pig) 



The genus H a li cho er u s is ])eculiar to the coasts and islands of 

 the North Atlantic. Only one species is known. 



