76 HISTORY OF THE EUROPEAN FAUNA. 



Plants being more directly affected than animals 

 by changes of temperature and rainfall, remarks 

 Mr. Clement Reid (p. 185), give evidence of the 

 highest value when we inquire into former climatic 

 conditions. The severity of the climate during the 

 Glacial period is often assumed from the occurrence 

 in pleistocene strata of such plants as Dryas octopetala^ 

 some species of willow, the dwarf birch, and others, 

 which are now found in high latitudes and in the Alps, 

 but are, as a rule, absent from the plain of Northern 

 Europe. Professor J. Geikie goes so far as to state 

 (p. 398) that it was unlikely that southern England 

 during the climax of the glacial cold had much if any 

 vegetation to boast of, and continues, " It is certain, 

 however, that it was clothed and peopled by an Arctic 

 flora and fauna when the climatic conditions were 

 somewhat less severe, relics of that flora having been 

 detected at Bovey Tracey." He believes, therefore, 

 that an Arctic flora took possession of England as 

 soon as the climate enabled it to live in the country. 

 Arctic plants, according to this explanation of the 

 sequence of events, were the first immigrants to 

 reconquer the dreary, plantless wastes and make 

 them habitable for mammals. 



Fortunately these views do not at all agree with 

 those of many of our leading European botanists and 

 others entitled to have a voice in the matter. Pro- 

 fessor Warming is of opinion that the main mass of 

 the present flora of Greenland survived the Glacial 

 period in that country (p. 403); whilst Professor 



