URSIDJE. URSINJE. URSUS. 479 



and from spring to late autumn they constantly roam the woods and 

 open places searching for food. Some Grizzlies are said to reach a 

 weight of 1,000 to 1,200 pounds, but such enormous beasts are rare, 

 the majority being very much smaller. It is not very unusual, how- 

 ever, to find one of these animals that will measure eight feet, and 

 even more, when standing erect upon its hind legs. In Mexico Bears 

 are found in the mountain ranges, sometimes at high altitudes. 



Fam. IV. Ursidee. Bears. 



True molars with broad, flat tubercular crowns; fourth upper 

 premolars with no inner root; bullae scarcely inflated; soles naked; 

 feet plantigrade. 



Subfam. I. Ursinse. 

 9O. Ursus. 



T 33. p lnJ. p 4=4- M 

 X -3-3' U i-i' *VV M '3-3- 42 ' 



C. H. Merriam. Preliminary Synopsis of the American Bears, 

 Proc. Biol. Soc. Wash., 1896, p. 65. 



Ursus Linn., Syst. Nat., i, 1758, p. 47; i, 1766, p. 69. Type Ursus 

 arctus Linnaeus. 



Thalassarctos! Gray, Ann. of Phil., 1825, xxvi, p. 339. 



Danis Gray, Ann. of Phil., xxvi, 1825, pp. 60, 339. 



Thalarctos! Gray, Ann. of Phil., xxvi, 1825, p. 62. 



Euarctos! Gray, Proc. Zool. Soc., 1864, p. 692. 



Size large; body heavy, bulky; three upper and under anterior 

 molars are very small and with but a single root, and are frequently 

 deciduous; fourth upper premolar lacks inner tubercle supported by 

 a separate root; fourth premolar larger than those before it, that in 

 upper jaw has three roots, the one in the lower two; skull elongate; 

 feet broad; toes armed with long, somewhat curved, non-retractile 

 claws; palms and soles naked; tail exceedingly short; ears erect, 

 rather short, hairy. 



KEY TO THE SPECIES. 



PAGE 



A. Front claws longer than hinder; fur shaggy. . . . U. horrioeus 480 



B. Front claws short, not longer than hinder; fur 



uniform, smooth U. machetes 481 



A. Danis. 



"Fur shaggy; front claws longer than the hinder, broadly de- 

 pressed, whitish; palate narrow and contracted behind; ears small; 

 hind foot elongate." 



