PRONGBUCK. 
3 2 7 
pletely disappeared from both these states. In latitude their range extended from 
the tropics to the 54th parallel; and within these limits they frequent by choice the 
open prairie country, avoiding thickly-timbered districts or high naked mountains. 
That the horns of the prong-buck were shed annually was long; 
Homs 1 * o 
and persistently urged by the hunters of Fort Union; but these 
statements were received with incredulity by naturalists, who scouted the idea. 
Eventually, however, it was proved to their satisfaction that the hunters were right 
and they themselves in error. In fully adult individuals, the annual shedding of 
the horns usually takes place during October, but in the young the horns are 
retained till January. In the males the horns can be felt as prominences beneath 
the skin even at birth, and at about four months old they burst through the 
skin. They are later in making their appearance in the females, and cannot be 
detected at birth. One of the best accounts of the shedding and replacement 
of the horns is given by Mr. Caton, from which the following summary is taken. 
On looking into the hollow of a shed horn, it will be found that the cavity does 
not extend much above the point of bifurcation; while it will be also noticed that 
the interior of the horn contains a number of coarse light-coloured hairs, all of 
which are firmly attached to its substance, while in the lower part many pass 
completely through it. The core from which the sheath was cast will also be 
found to be covered with similar hairs growing from an investing skin; and it 
will thus be evident that the sheath was more or less completely penetrated by a 
number of the subjacent hairs, which were of course torn asunder at the time of 
shedding. Indeed the horn of the prongbuck is in reality nothing more than 
a mass of agglomerated hairs, and thereby differs markedly from the bovine horn. 
On examining the head of a prongbuck from which the horns have been freshly 
shed, it will be observed that the summits of the cores are already capped with 
small new horns, which have evidently commenced their growth considerably before 
the period of casting, as they reach for several inches above the tips of the cores. 
The summits of these new horns are perfectly hardened, but lower down they 
gradually become softer and softer, until they pass into the skin investing the 
greater part of the core. The condition presented by an animal with newly-growing 
horns is shown in the woodcut on the following page. 
It is thus clear that as the new horn gradually increased in length above the 
summit of the core, it must have loosened and carried with it the old sheath, which 
eventually became completely detached from the core by the breaking and tearing 
away of the hairs passing from the skin into its substance. When nearly the whole 
of the hairs were detached or broken, any sudden motion of the animal would 
doubtless lead to the loss of the horns; but it does not appear that, at least as a 
rule, the process is assisted by the animal rubbing its horns against neighbouring 
objects. In regard to the renovating process, Mr. Caton writes that “when the old 
horn was cast off, the new one, as we have already seen, had made a considerable 
growth above the core, which was already tipped with perfected horn, while a section 
below it was more or less hardened, or partially converted into horn. This inter¬ 
vening section gradually moved down the horn, constantly invading the soft skin 
below, and followed above with perfected horn. All this time the horn was growing 
in length above the core, and assuming that posterior curvature near its upper part 
