82 
JOURNAL OF MAMMALOGY 
THE PRONG-HORN 
By M. P. Skinner 
[Plates 6-9] 
The prong-horn is found only in North America, where it is one of the 
most characteristic animals. It is peculiar in that the horn sheath is 
shed every year, leaving the core, which is an integral part of the 
skull, in place; in that the horns have a prong, hence the name, prong- 
horn; in that the coarse hair is of very peculiar form and character; and 
in that all the hair of the rump, surrounding a musk gland, can be 
erected. It has wonderful eyesight ; and is capable of great speed. 
Family ANTILOCAPRIDAE. Prong-horn Antelopes 
Closely allied to the Bovida?, but the horns deciduous and branched (Flower 
and Lydekker). 
Genus Antilocapra Ord 
Antilocapra Ord, Journal de Physique, vol. 87, p. 149. 1818. 
Type of genus. — Antilope americana Ord, 1815. 
0-0 0-0 3-3 3-3 
Dentition of genus. I — C — P — M — 32, 
3-3 1-1 3-3 3-3 
Characters of genus. — Bony horn cores unbranched, forming vertical, blade-like 
projections immediately above the orbits; horns compressed, about 250 mm. in 
length, in a straight line, or 400 mm. following the curves, having a gentle back- 
ward curvature, the short branch or prong arising about the middle of its height. 
When the horn is about to be cast off, it becomes loosened and a new one covered 
with long hairs, which soon disappear, is formed upon the bony core beneath it. 
The ears are long and pointed. Tail short and pointed, densely coated with 
coarse hair, except on the underside where the hairs are extremely short. The 
neck has a thick mane of long chestnut colored hair. Accessory hoofs are wanting. 
The lachrymal sinuses of the true antelopes are undeveloped; as also are the 
“inguinal pores,” or groin sacks found in true antelopes.^ 
SUBSPECIES 
Antilocapra americana americana (Ord), 1815. Described from the “plains 
and highlands of the Missouri,” and including most of the range of the Prong- 
horn. 
Antilocapra americana mexicana Merriam, 1901. Mexican Prong-horn Ante- 
lope. Described from Sierra en Media, State of Chihuahua, Mexico. Sonoran 
and Transition zones of northern Mexico, extending north into the United States, 
along the Mexican border. 
‘ Mearns, Bull. 56, U, S. Nat. Mus., pp. 220-221, 1907. 
