4 
The Mammals of Colorado 
a. Horns never branched, and retained through Ufe. (Bovidas.) 
a'. Horns smooth and rounded. Bison, p. 4 
b'. Horns transversely wrinkled and rough. Ovis, p. 9 
b. Horns branched and shed periodically. (Antilocapridae.) 
Antilocapra, p. 13 
B. Frontal appendages in the form of antlers, formed of true 
bone, and covered during growth with a vascular 
hairy skin; these are shed annually. (Cervidae.) 
a. Smaller; antlers without basal tines, only a single short, 
upwardly directed basal snag; tail long. 
Odocoileus, p. 18 
b. Larger; antlers with two basal tines forwardly directed; 
tail short. Cervus, p. 24 
Family BOVIDiE 
Frontal appendages, when present, consisting of a long 
bony process attached to the frontal bone, termed the horn- 
core; this is ensheathed with the true horn, which is there- 
fore hollow, and consists of an epidermic development of 
hard fibrous matter; these horns are not shed periodically, 
but remain in situ and increase in size during the whole life 
of the animal; dentition, i. ^; c. f; pm. f; m. f X 2 = 32; 
upper incisors and canines absent; lower canines resembling 
the incisors, and following them without a gap; molars 
usually hypsodont (i. e., with long crowns); lateral {i. e., 2d 
and 5th) digits usually completely absent, or represented by 
the small "false" hoofs; gall-bladder always present. 
Genus BISON. (The ancient Teutonic and Scandinavian name 
of the European form.) 
Bison, H. Smith in Griff., Anim.Kingd , v., p. 373 (1827). Type, 
B. bison Linnaeus. 
This genus contains that section of the Wild Oxen dis- 
tinguished by their rounded horns, their transversely arched 
foreheads, their prominent orbits, and the great develop- 
ment of hairy mane on the fore part of the body. Two 
species only are generally recognized, the European Bison 
{B. bonasus), now only existing in the primeval forests of 
