CHAPTER XIII. 
THE BLACK TAILED DEER— THE PRONG-HORN OR AMERICAN ANTE- 
LOPE-ROCKY MOUNTAIN GOAT— ARGALI OR ROCKY MOUNTAIN 
SHEEP— DESCRIPTION AND HABITS. 
The Black-tailed Deer ( Cervus Macrotis ) is found only 
near the Rocky Mountains and on the plains of Missouri, 
preferring generally the prairies to the woods. It was first 
noticed by Lewis and Clarke in their explorations ; they 
inform us that it resembles its kindred species, except that it 
does not run at full speed, but bounds along, raising every 
foot from the ground at the same time. In this it may be 
compared to the spring-bok of Africa. Its ears are very long, 
extending half the length of the antler. 
The American Antelope, or Prong-horn ( Antelocajora 
Americana ), fleeter than the swiftest horse, roams through 
the Rocky Mountains, keeping entirely to the open ground, 
migrating in winter to Mexico and California. So swift is it 
in its movements, and so acute is it in its sense of smell, that 
man rarely approaches it ; and the celerity with which the 
ground is passed over by it, resembles more closely the flight of 
a bird, than the motion of a quadruped. 
The only reliable accounts we have of it are from Long’s 
Expedition, and Lewis and Clarke’s observations, if we except 
the following from Wilke’s exploring expedition : “ An antelope 
was killed in Southern Oregon, near Rogue’s River ; it was 
of a dun and white colour, and its hair remarkably soft. The 
Indians take this animal by exciting its curiosity ; for this 
purpose they conceal themselves in a bush, near its hunting 
grounds, and making a rustling noise, soon attract its atten- 
tion, when it is led to advance towards the place of conceal- 
