22 THE TUNDRA AND ITS FAUNA 
Grinnell Land, and in the adjacent regions. It is 
non-migratory, finding food throughout the year by 
scraping away the thin covering of snow. A markedly 
social animal, the herds seem capable of defending 
themselves against the Arctic wolf, which attacks 
chiefly young stragglers. 
To this short list we should perhaps add the fact that 
the mammoth occurs in the tundra in the subfossil 
condition in Asia and also in Alaska. 
Rodents are represented in the tundra by the Arctic 
hare (Lepus glacialis), which is very abundant in suit- 
able localities. Even in winter it finds food enough in 
the grasses which project through the snow. Its 
greatest enemy is the wolf, which seems to feed largely 
upon it, but in spite of the abundance of that animal 
in King Oscar Land the Arctic hare is stated to be very 
abundant there. Another important rodent of the 
tundra is the lemming (Myodes torquatus), which is 
sometimes extraordinarily abundant. Absent from 
Spitsbergen, it occurs elsewhere on both sides of the 
Arctic region. Perhaps because of the paucity of 
vegetation in its natural habitat, this northern lemming 
does not show the enormous fertility of the Norwegian 
form, nor does it seem to migrate in the same fashion. 
In some regions, as in Nova Zembla, it is, however, 
remarkably abundant. While the other herbivorous 
animals named find their food in winter either by 
scraping away the snow, or by nibbling the protruding 
shoots, the lemming, a much smaller animal—it is not 
much bigger than a mouse—lives in winter beneath the 
snow, making runs and burrows in the underlying 
ground. When the snow melts in spring these runs 
appear, ramifying over the surface in all directions. 
The Norwegian lemming (M. lemmus) is also circum- 
