URSIDZ. URSINZE. 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. Ursidz. Bears. 
True molars with broad, flat tubercular crowns; fourth upper 
premolars with no inner root; bulle scarcely inflated; soles naked; 
feet plantigrade. 
Subfam. I. Ursinee. 
90. Ursus. 
eee C=; = MS = 42. 
C. H. Merriam. Preliminary Synopsis of the American Bears, 
Proc. Biol. Soc. Wash., 1896, p. 65. 
Ursus Linn., Syst. Nat., 1, 1758, p. 47; 1, 1766, p. 69. Type Ursus 
arctus Linneus. 
Thalassarctos! Gray, Ann. of Phil., 1825, xxvI, p. 339. 
Dams Gray, Ann. of Phil., xxvi1, 1825, pp. 60, 339. 
Thalarcios! Gray, Ann. of Phil., xxvi, 1825, p. 62. 
Euarctos! Gray, Proc. Zodl. 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. 
BEY TO); THE ‘SPECIES. 
PAGE 
A. Front claws longer than hinder; fur shaggy....U. horrieus 480 
B. Front claws short, not longer than hinder; fur 
MTP EIN, odie cs otis os. s Gael eb ce ele eel 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.”’ 
