FAMILY. 
CAVICORNIA. 
Ruminants with the horns permanent, hollow, and enclosing a process of the frontal bone. Incisors, 33 canines, none; 
molars, =a 
The above diagnosis in its first sentence expresses in brief terms the principal points in which 
the Cavicornia, or hollow-horned ruminants, differ from those with solid horns, the North 
American species of which have just been discussed. 
I have not the time, nor is the present the occasion, to go into a general discussion of the 
various systems of classification proposed by authors for the animals of the present group. In 
the limited number of species inhabiting North America, it will be sufficient to state, that, of 
the several divisions of the family, namely, the antelopes, the goats, the sheep, the musk oxen, 
and the bulls, America possesses a representative of all, excepting the goats, the Rocky Mountain 
goat of authors being really an antelope. The following synopsis will serve to show how the 
different genera are related to each other. 
A. Awntitopinar.—Horns rounded or conical, without sharp angles; variously curved; annulated or wrinkled. Muzzle 
elongated, attenuated, end of upper lip with a shallow groove ; generally hairy. 
Antilocapra—F alse hoofs, none. Horns rounded and recurved at tip, broadly compressed at base, with an angular process 
in front. 
Aplocerus.— With false hoofs. Horns conical, nearly erect, slightly recurved. Hair long and silky. 
B. Ovinar.—Horns more or less angular and compressed, usually twisted and curved backwards, wrinkled. Muzzle broader 
than in the last ; hairy, except sometimes between the nostrils ; with a shallow groove. 
Capra.—Horns curving backwards. Head, without any lachrymal sinus. Nose for the most part straight in its upper outline ; 
chin bearded.* 
Ovis.—Horns curved backwards, and variously twisted so that the tip is brought forwards again. Head with a distinct 
lachrymal sinus. Upper outline of nose curved. Chin without a beard. 
Boyinar.—Horns rounded. Muzzle broad, without any vertical furrow at the end, usually naked. 
Ovibos.—Horns curving outwards and downwards. Muffle hairy, except between the nostrils. 
Bos.—Horns curving outwards and upwards. Muffle entirely naked to the edge of the lip. 
The number of species of the antelopes is very great, the latest list I have seen (that of 
Wagner, 1855,) embracing about ninety species: of these, two belong to North America, 
Aplocerus montanus and Antilocapra americana ; two to Europe, the gazelle, Antilope saiga, and 
the chamois, (Capella rupicapra) ; nearly all the rest to Africa. It is not a little remarkable 
that the entire family of hollow-horned ruminants should be altogether wanting as original 
species in South America. Of the Ovinae, including the sheep and goats, America has but one 
species, nearly all being confined to the mountainous portions of Asia and Europe. Of the 
Bovinae, there are not many species, (about ten in all); two are North American, one European, 
the rest belong to Africa and Asia. The affinities of Ovibos are more strictly with the sheep, 
however, and a natural arrangement would probably place them there, as has been done by 
some authors. 
1 The common domestic goat is our only representative of this genus, the so-called Rocky Mountain goat being truly an 
antelope. 
