210 HISTORY OF THE EUROPEAN FAUNA. 



discovered, must have possessed tundras and steppes, 

 as we find them nowadays in Siberia, and a climate 

 similar to that of Northern Asia. It is presumed 

 that the climate, after the maximum cold of the first 

 stage of the Ice- Age, ameliorated so far as to permit 

 these mammals to exist in Europe. 



The natural question, however, which is forced 

 upon us in reading Professor Nehring's interesting 

 and suggestive work is, where did all these steppe 

 animals live during the earlier part of the Ice- Age? 

 No traces of their remains have been discovered in 

 Southern Europe, and it can therefore certainly be 

 affirmed that they could not have lived there. If 

 Central and Northern Europe were uninhabitable 

 for mammals, Central and Northern Asia must have 

 been even more so, and we have to fall back upon the 

 Oriental Region as a possible home of these species 

 during the assumed maximum cold of the Glacial 

 period. In invading Europe from the Oriental 

 Region these Siberian mammals would have taken 

 the shorter route by Asia Minor and Greece, which 

 was open to them. This they certainly did not do, 

 which proves that they came directly from Siberia to 

 Europe without retreating first to Southern Asia. 



But it seems to me that there is no necessity for 

 assuming such drastic changes of climate to have 

 taken place at all (compare pp. 75-80). We really 

 have no idea under what precise climatic conditions 

 the Siberian mammals lived in their original home. 

 The only thing we can be certain of is that the 



