WHITENESS IN POLAR REGIONS 



have even gone so far as to assert that the change is 

 rare or never occurs, and that in consequence the two 

 forms are two forms, and not merely seasonal varieties. 

 There is no doubt, however, that the change does take 

 place ; for foxes at the Zoo have been known to put off 

 one coat and take on the other. In Spitzbergen, and in 

 all such very northerly latitudes, the change takes place ; 

 but in Iceland, the southernmost land inhabited by this 

 fox, there is no change in winter, a case which is paralleled 

 by the polar hare of this country, which changes to 

 white in winter in Scotland, but not in the damper, and 

 thus warmer, Ireland. Though now limited to the 

 frozen north, this fox in former days wandered farther 

 south, as its fossil remains in this country show. The 

 same is true of many animals now definitely confined to 

 polar latitudes, such as the polar bear and the reindeer. 

 This fox feeds upon ptarmigan or any birds that it can 

 get, and upon cast up carcasses of seals and whales ; it 

 is also fond of shell- fish and of eggs. In the winter 

 of the north it is difficult for it to get any food at all, 

 and it has been suggested that it stores up food when 

 there is a surplus for a rainy or, better perhaps, a snowy 

 day. But the exact observation wanting to confirm such 

 a story appears to be lacking so far. It is described as 

 uttering a " yapping bark." It is called a fox mainly 

 because of its small size and long tail. The dogs, 

 wolves, j ackals and foxes, form in reality a highly uniform 

 assemblage of carnivores. By certain small skull 

 characters it is possible to separate a fox-like series from 

 a wolf-like series. Viewed in this way, Azara's fox of 

 South America is a wolf and a jackal is a wolf ; but the 

 Reynard of England, as well as its arctic ally, is a fox. 

 To those who have not had the opportunity of examining 

 the bones the jackals suggest a fox rather than a dog or 

 wolf. But probably no one would doubt the fox-like 

 nature of Canis lagopus, the arctic fox. 



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