HISTORY OF THE EUROPEAN FAUNA. 



probably in both. The Alps no doubt produced a 

 number of species which have spread north and 

 south, and may in their wanderings have joined the 

 Siberian migrants in their western course, and thus 

 have reached the British Islands. Nevertheless, the 

 majority of the mammals belonging to the eastern 

 clement of the British fauna (vide p. 95) have un- 

 doubtedly originated in Siberia. The Polecat (Mus- 

 tela putorius} and the Harvest Mouse (Mus minutus], 

 for instance, are members of that eastern migration. 

 Both occur throughout Central Europe and a large 

 portion of Siberia, but are absent from the extreme 

 north and south of Europe and also from all the 

 Mediterranean Islands. A Siberian species, which 

 has never penetrated so far west as the British 

 Islands, nor even so far north as Scandinavia or 

 south to Italy, is what is known in Germany as the 

 "Hamster" (Cricetus frumentarius], a little Rodent 

 which spends the winter asleep in its burrows, and 

 surrounds itself with a great accumulation of food- 

 material carried there during autumn. The common 

 English Hare, which I formerly regarded as an 

 instance of a Siberian mammal, must now find a 

 place among the Oriental migrants. Its history is 

 very instructive, and I shall have an opportunity later 

 on to refer to it again. Meanwhile, it may be men- 

 tioned that though this Hare inhabits Europe in two 

 varieties or races, one of which, Lepus mediterra- 

 neus, is confined to Southern Europe, the latter owes 

 its origin to an earlier migration from Asia. 



