60 MOUNTAIN AND MOORLAND 



British Islands, and subsequently another migration 

 had begun to come in from the south-east. The 

 climate had meanwhile gradually become more tem- 

 perate and drier. About the same time, or even 

 earlier, an Arctic migration commenced to pass 

 southward, and finally the Siberian animals poured 

 into our continent/ 1 



The northern contingent may be illustrated by the 

 Mountain Hare, the Stoat, the Ptarmigan, the Red 

 Grouse, the Stickleback and the Miller's Thumb. A 

 Siberian migration probably brought us animals like 

 the Polecat and the Harvest Mouse, the Common 

 Shrew and the now exterminated Beaver. To an 

 Oriental migration, closely related to the Siberian, 

 may be credited such animals as Red Deer and Rats, 

 Water-Ouzels and Bullfinches. From South-western 

 Europe may have come the Rabbit and the Pied Wag- 

 tail and the Irish Spotted Slug. To the Alps we may 

 owe a few contributions, such as the Dormouse. We 

 cannot, however, do more than raise the difficult ques- 

 tion of the origin of our fauna and flora, and mention 

 Dr. ScharfFs book as the most convenient to start 

 with in finding out answers. 



