PROPOSED EXPLORATIONS AND INVESTIGATIONS 255 



7. Origin of the Present Fauna of Europe. — Considerable light lias 

 of late years been thrown on the question of the origin of the Euro- 

 pean fauna ; yet while certain general propositions may be said to 

 have gained common acceptance because based on fairly convincing 

 evidence, man}^ others are based chiefly upon more or less plausible 

 theories, for which the proof in the shape of sufficient material is 

 still lacking. On the other hand, there are numerous important 

 questions where the opinions and theories of those best equipped to 

 judge are diametrically opposite, not because the nature of the ques- 

 tions is such as to preclude an indisputable settlement, but simply 

 because there is not material in any one museum, nor even in all 

 museums, adequate to establish the status of the species or their 

 geographical distribution. 



It would be impracticable in the present connection to go into 

 detail with regard to all these questions or to prove the above asser- 

 tion for the various classes of animals. It must suffice to mention 

 a few flagrant cases which may stand as examples of the rest. 



One of the most important problems, as far as the origin of the 

 European fauna is concerned, is the question whence came the 

 animals which Doctor Scharff has termed the "Arctic migration." 

 He, with many others, contends that until toward the end of the 

 glacial period there existed a continuous land connection between 

 America and Europe, far north between Greenland, Spitzbergen, 

 and Scandinavia, the latter being again connected by a land bridge 

 with Scotland across the North Sea, and England with France. 

 Across this continuous land bridge these animals are supposed hy him 

 to have wandered into central Europe. One of the writers has tried 

 to disprove this hypothesis, both on physiographical and biological 

 grounds, and has advanced the theory that these animals reached 

 central Europe and Great Britain from western Siberia before the 

 maximum glaciation, and that from Scotland they extended into 

 western Norway. Unfortunately, however, there is nowhere any 

 material gathered together which would help settle the question. 



It is unnecessary to here detail the gaps in our knowledge which 

 make a discussion of this question a mere guessing contest. Suffice 

 it to say that some of the most elementar}^ facts concerning the rela- 

 tions and distribution of some of the largest, most conspicuous, and 

 most important species are in dispute. Indispensable details as to the 

 distribution and relationships of the ermine, the lemmings, the deer, 

 the reindeer, the grouse, the ptarmigan, etc., are still lacking and, 

 except by some lucky chance, may not be forthcoming for a long 



