cal NORTH AMERICAN RUMINANTS 
covered externally with ‘short, thick, velvety fur, which con- 
sists of a network of blood vessels which supply nutriment for 
the growth of the antler. During this stage the antlers are said 
to be “in the velvet,’’ and are then very sensitive to injury. 
When fully grown, the membranous covering shrivels and dries 
up, and falls off in shreds or is rubbed off by the animal. 
The horns of the hollow-horned Ruminants are entirely differ- 
ent from the antlers of Deer, in structure as well as in manner of 
growth. They are usually common to both sexes, as__ gorns of 
in our domestic cattle, are simple and not branched, Oxen, 
and grow continuously throughout the life of the ani- Sheep, ete. 
mal, though very slowly after it has reached maturity, and are 
never shed. They consist of a bony core—an elongated process 
from the frontal bone—covered with horn, from which the organ 
takes its name, and which is easily removed by maceration, or 
through decomposition after the death of the animal. This outer 
shell is the true horn, the bony core is its support. 
The American Pronghorns offer a quasi exception to this 
division of Ruminants into solid-horned and hollow-horned sec- 
tions. .They have the permanent bony horn-core of the hollow- 
horned division, with an outer horny sheath, which is annually 
shed and renewed, as are the solid antlers of the Deer tribe. 
They are, however, usually assigned to the solid-horned or 
antlered section of Ruminants. 
FAMILIES OF NORTH AMERICAN RUMINANTS. 
Technically speaking, the Ruminant game animals of North 
America consist of three distinct families, two of which are 
represented by several genera, and some of the genera by numer- 
ous species. These families are, the Pronghorns, family A ntilo- 
capride; the Deer, family Cervide, and the Sheep, Goat and Ox 
tribes, forming the family Bovide. These will be now passed in 
review, with special reference to their present representation in 
the American Museum. The geographical area covered in this 
connection by the term North America includes the whole North 
American continent from the Arctic regions to Panama. 
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