NARWHAL. 



CHAPTER IV 



Mammals and Birds of the Arctic 



The beautiful Arctic fox (Canis lac/opus), so valued on account of 

 Arctic Fox. , . . ... 



its fur, is unique among mammals m presenting two distinct colour- 

 phases in the same locality at the same time of year. In winter, for instance, 

 some of these foxes are pure white, while others are pale slaty blue ; and there is 

 a difference, although less marked, between the summer coats of the two phases. 

 Arctic foxes range northward from Iceland and Norway to Grinnell-land. 



Even more Arctic in its distribution is the polar bear (Ursus 

 Polar Bear. ... . 



maritimus), which retains its snowy livery at all seasons. This 



animal is met with both on ice-girdled shores and the open ice-fields, but is rarely 



seen in large parties. Generally, indeed, a male and female, often accompanied 



by one or two cubs, wander about in company, but where sealers and whalers have 



left the carcases of their victims in large numbers, there the bears will frequently 



collect to enjoy the banquet. Seal and whale flesh and blubber form, indeed, the 



main food-supply of the polar bear, but in some districts quantities of fish, 



especially salmon, are consumed by them, and, in summer, grass, lichens, and 



seaweed are eaten with relish. Although some polar bears undoubtedly migrate 



in winter, males and cubs being often seen at that season much farther south than 



in summer, it is possible that many old males hibernate in the far north, and the 



females certainly do so, or at least retire beneath the snow before the birth of 



their young. 



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