Americanus), in the arctic fox (Canis lagopus), in the stoat and ermine, and among birds, in the ptarmigan, and some other species of Lagopus.
The land mammals of Greenland are decidedly more American than European; the musk-ox, the banded lemming (Cuniculus torquatus), the white polar wolf, of which there seems to have been a new invasion recently round the northern part of the country to the east coast, the Eskimo and the dog - probably also the reindeer - have all come from America, while the other land mammals, the polar bear, the polar fox, the Arctic hare, the stoat (Mustela erminea), are perfectly circumpolar forms. The species of seals and whales are, if anything, more American than European, and so to some extent are the fishes.
The fox (Canis vulpes), the stonemarten (Mantes foina) and the stoat or ermine (Putorius erminea) range in summer above the tree-limit.
In cold regions the weasel turns white in winter, but less regularly and only at a lower temperature than the stoat or ermine, from which it is distinguished by its smaller size and the absence of the black tail-tip. The length of the head and.