260 BULLETIN NO. VII. 
of origin of the genus. Two species of smaller but still con- 
siderable size then appeared, one in|Hurope the other in Am- 
erica. B. priscus of Europe and B. antiquus of America may 
reasonably be assumed as the forerunners of the existing 
aurochs and the American bison. These differ from each other 
apparently more than the two earlier species from which they 
sprang. 
The B. latifrons must have been of enormous size, the horns 
being in the male not less than six feet long. The horn cores 
at the base measure 20 inches, the forehead being over fifteen 
inches wide. The existing remains were derived from Ken- 
tucky, Texas and Mississippi, associated in some instances 
with the mastodon and horse, as well as other extinct species. 
Bison antiquus is known from quite a variety of remains, but 
so imperfect are they all that it remains a question whether 
they are not specifically identical with B. latifrons or perhaps 
with the extinct European B. priscus. The evidence seems to 
favor the existence of a species smaller than B. latifrons, but 
still of greater size than our living species characterized by 
larger proportional horn cores and other differences. The 
remains referred to have been found in California, Alaska and 
Kentucky, and in connection with extinct elephants, tapirs and 
horses. For a discussion of the evidence bearing on these 
matters, refer to Allen’s monograph, forming Part II, of Vol. 
I, of the Kentucky Geological Survey Memoirs. It would be 
of interest if it were possible to determine from what time our 
modern species dates, yet, although the species is found fossil 
in the bone caves of Pennsylvania and the deposits of Big-bone 
Lick, Kentucky, we only can conclude that its remains are 
always later than those of the mammoth and mastodon, and do 
not reach a great antiquity. Prof. Shaler thinks it probable 
that the bison did not co-exist with the mound-builders. 
Bison americanus GMELIN. 
Plate IV. 
We rely in many details of the description upon that given 
by J. A. Allen and refer the reader to his monograph for bibli- 
ography. 
An adult male measures about nine feet from the muzzle to 
the root of the tail—thirteen and one-half feet to the end of the 
tail. The female measures six and one-half feet to the inser- 
