THE GAME ANIMALS OF CANADA he 
described by E. W. Nelson in 1884. A fourth species, 
known as Fannin’s mountain sheep, or the ‘‘saddle-backed”’ 
or ‘‘piebald”’ sheep (Ovis fannini), was described by W. T. 
Hornaday in 1901.* This species is now considered by 
some to be due to interbreeding between Ovis stoner and 
Ovis dalli. Its type specimen is in the Provincial Museum 
at Victoria, B. C., and the latter view appears to me to be 
correct in view of the observations of Charles Sheldon{ and 
others. 
An examination of many skins and the reports of hunters 
indicate a strong tendency among the northern mountain 
sheep to vary in colour and thus render specific designations 
somewhat difficult. In northern British Columbia and the 
adjoining part of the Yukon Territory where Fannin’s sad- 
dle-backed sheep occurs, in the mountains between the home 
of the typical Stone’s black mountain sheep (O. stoner) and 
Dall’s white mountain sheep (0. dalli), sheep are found hav- 
ing white heads and necks and with bodies of varying shades 
of grey, produced by mixtures of dark and white hairs. 
One may find white sheep mingling with the dark-grey or 
grey and white sheep. There can be little doubt that in- 
terbreeding occurs. But, while such intergrading of char- 
acters may be found in regions adjoining or common to 
different species, especially as mountain sheep will occasion- 
ally extend their range, in the mountain ranges where in- 
termingling does not occur the animals keep true to type, 
the topographical and climatic conditions being sufficient 
to prevent extensive intermingling. The distribution of 
the colour variations intermediate between the black O. 
stonet and the white O. dalli, including the ‘‘saddle-back”’ 
sheep, O. fannini, is shown in the accompanying map pre- 
*Hornaday, W. T., “ Notes on Mountain Sheep in North America, with 
a Description of a New Species,” Fifth Ann. Report New York Zool. Society, 
pp. 77-122, 1901. 
+ “The Wilderness of the Upper Yukon.” By Charles Sheldon. Second 
edition, New York, 1909. 
