6o 



HISTORY OF THE EUROPEAN FAUNA. 



still possible. The occurrence of many Scandinavian 

 species in Scotland which are absent on the continent 



^r 



FIG. 4. Map of the British Islands and surrounding area at a time 

 when the earlier members of the southern migration reached 

 England. (Only some of the rivers have been indicated. The 

 shaded parts represent water, the light land.) 



of Europe, indicates that these two countries also 

 were united formerly. Most geologists hold that such 



