146 EVOLUTION, OLD AND NEW. 



have travelled either over some land still unknown, or 

 " more probably," over territory which has long since 

 been submerged. The species of the old and new 

 world are never without some well-marked difference, 

 which however should not be held sufficient for us to 

 refuse to admit their practical identity. But he main- 

 tains, I imagine wiKuUy, that there is a tendency in 

 all the mammalia to become smaller on being trans- 

 ported to the new world, and refers the fact to the 

 quality of the earth, the condition of the climate, the 

 degrees of heat and humidity, to the height of moun- 

 tains, amounts of running or stagnant waters, extent of 

 forest, and above all to the brutal condition of nature in 

 a new country, which he evidently regards with true 

 aristocratic abhorrence.* 



Then follows a passage which I had better perhaps 

 give in full : — 



The mammoth " was certainly the greatest and 

 strongest of all quadrupeds ; but it has disappeared ; 

 and if so, how many smaller, feebler, and less remarkable 

 species must have also perished without leaving us any 

 traces or even hints of their having existed? How 

 many other species have changed their nature, that is 

 to say, become perfected or degraded, through great 

 changes in the distribution of land and ocean, through 

 the cultivation or neglect of the country which they 

 inhabit, through the long-continued effects of climatic 

 changes, so that they are no longer the same animals 

 that they once were ? Yet of all living beings after 



♦ Tom. ix. p. 107 and following pages (during which he rails at the 

 new world generally), 1761. 



