LEMMING AND ARCTIC HARE 
9 
remains which have been discovered in caves and other super¬ 
ficial (Pleistocene) deposits in Pennsylvania, Kentucky, Mis¬ 
souri, Iowa and Ohio may have belonged to varieties of Ovibos 
moschatus rather than to extinct species of musk oxen. 
There are two other arctic mammals which are of special 
interest to us, since both of them inhabit Greenland. They 
are the arctic hare (Lepus variabilis = L. timidus) and the arctic 
lemming (Dicrostonyx torquatus = Cuniculus torquatus). 
Like the reindeer, the arctic hare is subject to great varia¬ 
tion over the vast area which it inhabits, and some of these 
varieties or races are now recognised by many zoologists as 
species. Mr. R. Brown * * * § long ago felt the difficulty, nay, 
almost impossibility, in discriminating between the Green¬ 
land hare and the arctic or varying hare of Europe. The same 
embarrassment has confronted many subsequent authors. In 
America the Greenland hare is now generally considered as 
specifically distinct from the arctic American hare, Mr. 
Rhoads f having pointed out some important features in its 
incisor teeth, while Mr. Nelson ^ finds that its excessively 
heavy wool-like coat of fur, the long claws and tapering upper 
mandible sufficiently distinguish it from its relatives on the 
American Continent to give it the rank of separate species. 
However, as Mr. Rhoads aptly remarks (p. 356) the peculiar 
dentition, long fur, and long claws are due partly to the 
scantiness and character of plant life, and partly to the depth 
and long continuance of the snow in Greenland. These fea¬ 
tures seem to have gradually impressed themselves on the 
Greenland hare in modifying it in the direction indicated. 
In Major Barrett-Hamilton’s § opinion the chief differences 
between the European arctic hares and the Greenland form, 
from an external point of view, are only of a sub-specific 
value, while Dr. Winge || does not specifically distinguish the 
American or European arctic hares from the Greenland one. 
The same problem of affinity has recently been investigated 
from a new standpoint by Mr. Hinton. His researches have 
* Brown, R., “Mammals of Greenland,” p. 351. 
t Rhoads, S. N., “ Polar Hares of North America,” p. 368. 
X Nelson, E. W., “ Rabbits of North America,” p. 68. 
§ Barrett-Hamilton, G. E. H., “The Variable Hare,” p. 92. 
|| Winge, H., “ Gronlands Pattedyr,” p.376. 
