KEY TO LAND MAMMALS OF NORTHEASTERN NORTH AMERICA I39 



Genus Ursus Linnaeus 



1758 Ursu s Linnaeus, Systemanaturae. ed. 10. 1: 47. Type Ursus aretos 

 Linnaeus. 



Head short and broad; cheek teeth large and strong relatively to size of skull ; 

 color never white. (Ursus; Lat., a bearj 



The distribution of the genus Ursus is essentially the same as that 

 of the family to which it belongs. The species are at present little 

 known; probably 30 or more forms will eventually be recognized. 

 About a dozen occur in North America, only one of which is certainly 

 known within our limits. It is a member of the subgenus Euarctos. 



Ursus americanus Pallas Black bear 



Front claws slightly if at all longer than the hind ones; color black or 

 dark brown, the exact shade variable ; length of skull under 350 (13f). 

 (americanus; N. Lat., American) 



The black bear is widely distributed in North America from Mexico 

 and the gulf states northward. It is divisible into numerous geo- 

 graphic races, at least two of which occur within our limits. 



SUBSPECIES OF URSUS AMERICANUS 



Length of adult skull about 250 (9|) U. americanus americanus 



Length of adult skull about HOO (8) U. americanus sornborgeri 



Ursus americanus americanus Pallas Northern black bear 

 1780 Ursus americanus Pallas, Spicilegia zoologica. fasc. 14, p. 5. (North 



America) 

 1896 Ursus americanus Merriam, Proc. biolog. soo. Washington. 13 Ap. 

 1896. 10 : 79. 

 Skull long and narrow, its greatest length about 250 (9J). (americanus; 

 N. Lat., American) 



The northern black bear is abundant throughout the wilder forested 

 parts of the boreal and transition zones of eastern North America. The 

 characters of the bear inhabiting the austral zones are not at present un- 

 derstood. 



Ursus americanus sornborgeri Bangs Labrador black bear 

 1898 Ursus (Euarctos) americanus sornborgeri Bangs, Ameri- 

 can naturalist. July 1898. 32 : 500. (Okak, Labrador) 



Skull broad and short, its greatest length about 200 (8). (sornborgeri; 

 name from that of J. D. Sornborger) 



The Labrador black bear, known only from the skull, is common 

 throughout Labrador north of the tree limit. 



A large bear related to the grizzlies (perhaps Ursus richardsoni) 

 probably occurs on the barrens of interior Labrador. The species 

 has not yet been determined. 



