SCAPHOCEROS. TYRRELLI, AN: EXTINCT RUMINANT 
FROM THE KLONDIKE GRAVELS 
By WILFRED H. OSGOOD 
While engaged in work for the U. S. Biological Survey in the 
summer of 1904, I spent some days in Dawson, Yukon Territory. 
During this time I was so fortunate as to make the acquaintance of 
Mr. J. B. Tyrrell, formerly of the Geological Survey of Canada, and 
well known for his long and difficult trips through the great Barren 
Grounds west of Hudson Bay. Mr. Tyrrell’s interest in natural 
history led him_to preserve certain fossils found by himself and 
others in the Klondike region. Among these were two imperfect 
skulls of supposed musk oxen which he very generously presented 
to me for deposit in the U. S. National Museum. One of these is 
extremely well preserved. The characters of practically the entire 
skull are well shown, the chief missing parts having been lost from 
one side only. The molars and premolars of the left side and the 
second and third molars of the right side are intact. The skull is 
evidently that of a very old individual, as the teeth are much worn. 
The bone is lightly scratched by gravel over much of its surface, but 
the spaces between the scratches are smooth and evidently in original 
condition, so it does not appear that the form and dimensions of any 
of the bones have heen materially altered. The bone is of a dark 
brown color and not impregnated to any degree with mineral matter. 
The second specimen is much less complete, comprising only the pos- 
terior part of a skull and one attached horn core. 
These specimens represent an animal evidently related to the ex- . 
isting genus Ovibos, but sufficiently different to rank as a separate 
genus, for which a name is here proposed. The species called O. 
cavifrons by Leidy is closely related and falls in the same genus. 
O. maximus of Richardson possibly belongs here also, but for the 
present can only be considered indeterminate. The genus Bodther- 
tm, in which O. cavifrons was included by Leidy, is recognized as 
distinct, with Bos bombifrons Harlan as the type. 
For the privilege of describing this interesting fossil, I am in- 
debted to Dr. C. Hart Merriam, Chief of the U. S. Biological Survey. 
In connection with the study, I have been greatly assisted by the 
loan of specimens from Dr. F. W. True, of the U. S. National Mu- 
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