CLASS MAMMALIA 669 



pig; is nocturnal; goes about in companies; and feeds on nuts 

 and roots. 



The deer (Cervid^e) constitute the majority of the American 

 hoofed mammals. Their horns or antlers are solid, and are shed 

 annually. The best-known species are the wapiti or elk, Vir- 

 ginia deer, mule deer, with round horns, and the caribou and 

 moose, with flat horns. 



The moose, Alces americanus, is the largest member of the 

 family and possesses the most massive antlers. It inhabits the 

 woods of the northern United States and British America, and 

 feeds on bark, twigs, leaves, moss, and lichens. A larger and 

 darker race occurs in Alaska. The woodland caribou, Rangifer 

 caribou, lives in the forested parts of northern Maine and Mon- 

 tana, and British America. The female caribou is our only 

 female deer that bears antlers. The reindeer also belongs to the 

 genus Rangifer. 



The wapiti or elk, Cervus canadensis, is the largest round- 

 horned deer. It is easily bred in confinement, and is common 

 in zoological parks. The Virginia or white-tailed deer, Odocoi- 

 leus virginianns, is the best known and most widely distributed 

 of all our species. It is an inhabitant of forests. The mule 

 deer or black-tailed deer, Odocoileus hemionus, is a large, high- 

 headed species, which prefers open country. It browses on 

 twigs and leaves, and also grazes when the grass is good. Two 

 fawns are usually produced at a birth. 



The pronghorn antelopes (Antilocaprid^e) are confined 

 to the open country of western North America. Their horns 

 are hollow, branched, and shed annually. There is but a single 

 species, Antilocapra americana. 



The family Bovid^e contains the gnus, hartebeests, dik-diks, 

 waterbucks, gazelles, elands, chamois, Rocky Mountain goats, 

 sheep, goats, musk-oxen, oxen, and bison. These are all rumi- 

 nants (see p. 668), and both males and females usually possess 

 unbranched, hollow horns, which fit over bony prominences on 

 the skull and are not shed annually. The best-known Ameri- 



