46 OKIGIN OF LIFE IN AMERICA 



tained by Professor Whitney.* and was supported by weighty 

 arguments, while Sir Henry Howorth f has contributed addi- 

 tional testimony in favour of a mild climate having prevailed 

 during the so-called Glacial Epoch or Ice Age. 



That extensive glaciers existed during that Epoch in 

 western Europe and north-eastern North America is pri- 

 marily due to the closing of the North Atlantic. This pro- 

 duced a rise of temperature in the Atlantic Ocean and intense 

 precipitation over western Europe, particularly Scandinavia, 

 and also .over north-eastern America, especially Labrador. 

 As Professor Whitney observes, the regions mentioned are the 

 only two in the world in which the topographical and climatic 

 conditions seem to have been considerably different during the 

 Glacial Epoch from what they are at present. The prevail- 

 ing opinion, however, among geologists is, that not only was 

 there -a centre of glaciation in Labrador, but also in the 

 Keewatin district to the west of Hudson Bay. The latter being 

 a perfectly flat region, without even a suggestion of a moun- 

 tainous nucleus, constitutes, indeed, as Professors Chamberlin 

 and Salisbury J acknowledge, one of the most marvellous fea- 

 tures in ice dispersion. All our notions as to the behaviour of 

 glaciers are derived from careful observations on .existing ones. 

 But nowhere on earth can a glacier be seen which, having 

 originated on level land and developed quite independently of 

 any adjacent higher region, proceeds to invade the neigh- 

 bouring areas. Hence a biologist may be excused for express- 

 ing some hesitation in accepting so extraordinary an hypo- 

 thesis in spite of the fact that we ar'e assured that the days 

 of reasonable doubt as to the former existence of these almost 

 inconceivably large ice-fields are past. 



To attempt even to discuss all the various lines of evi- 

 dence which have led to the almost general acceptance of the 

 land-ice theory, as understood at the present day, would be 

 impossible in ,a work of this nature. I only wish to bring 

 forward some of the chief reasons which have prevailed upon 

 me to reject this theory. I qan scarcely venture to hope that 



* Whitney, J. D., " Climatic Changes," p. 321. 



t Howorth, H. H., "Ice or Water," Vol. II., p. 492. 



I Chamberlin, T, C,, and B, D. Salisbury, " Geology," III., p. 332. 



