THE ARCTIC FAUNA. 135 



resembles in size the smaller varieties of Oxen, but in 

 structure and habits is closely allied to the Sheep. As 

 is implied by the specific name, it exhales a musky 

 odour ; this does not, however, appear to be due to 

 the secretion of a special gland, as is the case in other 

 animals with a similar smell. The skin is covered 

 with long brown thickly-matted hair, interspersed 

 with white. It is confined to the most northerly 

 parts of North America and the American Arctic 

 islands, and to North Greenland. Though not now 

 living in the Old World, it seems formerly to have 

 been abundant in Siberia, and, as we shall learn later 

 on, it was one of the species which took part in the 

 great Siberian invasion of Europe. Its remains have 

 been found not only in Germany and France, but also 

 in the south of England. 



The Polar Fox (Cants lagopus] occurs throughout 

 the Polar Regions, and on islands where even the 

 Reindeer and the Musk-Ox are unknown. Beyond 

 the Polar Circle, its range extends into Northern 

 Asia, to the extreme north of North America, and the 

 mountains of Scandinavia. Like its congeners, it 

 had in pleistocene times a more southerly extension, 

 and fossil remains have been met with in various 

 parts of continental Europe and in England. 



The Stoat (Mttstela erminea\ which is known and 

 much valued in commerce under the name of Ermine, 

 was formerly believed to occur only in Arctic America 

 and the northern parts of the Old World, but in more 

 recent years it has been discovered in a number of 



