SKINNER — THE PRONG-HORN 
85 
In summer the hair of the prong-horn is smooth and flexible, but as 
winter approaches it lengthens; each hair becomes thick, the interior 
whitens and grows spongy, and it loses flexibility, at last becoming 
brittle, so that its point is easily rubbed off. It also loses its elasticity, 
so that when once bent it will not straighten again. A coat of fine, 
white fur is found next the skin, particularly in winter; and forms a 
close and warm covering for the wearer. Doctor Murie has shown that 
the prong-horn is peculiar among ruminants in possessing hair with 
markedly denticulate cells in the medulla. In the spring, usually during 
the latter part of March in the Yellowstone, the long hair is shed, 
beginning about the face, and is replaced immediately with shorter 
hair that has started to grow previous to the shedding. 
In female prong-horns the horns are sometimes absent or abortive, 
occasionally quite large, but usually range from one to three inches 
long and are not branched; the horns of the adult female are invariably 
much smaller than those of the buck. The rudimentary horns may be 
detected on the buck at birth, but not so in the case of the doe. The 
prong-horn differs from the true antelopes in the deciduous nature of 
the horny sheaths covering the cores. It is interesting to observe that 
an early printed statement about the shedding of an antelope’s horns 
was a denial by Audubon and Bachman (1851), that they could be shed 
at all. This in spite of the fact that hunters at Fort Union (now Buford, 
N. D.) reported to Audubon that the prong-horns did shed and renew 
their horns annually. And from that date down to the present time 
the controversy has cropped up at recurrent intervals, although it has 
been definitely known for some time that the horns are regularly shed, 
but that the method and details are quite different from those of other 
animals. Here in the Yellowstone, at least, every buck prong-horn 
sheds his horn sheaths every year during November and December. 
At that time of year, our animals are on a restricted range and it is 
comparatively easy to find them all. In the course of several seasons 
I have noted that bucks with old horns are to be seen until the early 
part of December, and, after that time, all fche bucks are growing new 
horns. No complete horns are again seen until the first of the new 
horns have finished their growth towards the end of January. 
The horn cores (which are not shed) are spikelike, rising over the 
great eye orbit and leaning outward, and are not branched. They 
are essentially processes of the frontal bone of the skull, consisting of 
simple flattened blades of the bone, and are covered by the horny 
sheath which has a decurved tip and a prong, the latter a short triangular 
