70 CHARLES DARWIN. 



will tend to " exterminate its less well-fitted parent." This 

 explains classification, in which the organic beings " always 

 seem to branch anTl sub-branch like a tree from a common 

 trunk ; the flourishing twigs destroying the less vigorous the 

 dead and lost branches rudely representing extinct genera 

 and families." 



In a postscript he says : 



" This little abstract touches only the accumulative power 

 of natural selection, which I look at as by far the most im- 

 portant element in the production of new forms. The laws 

 governing the incipient or primordial variation (unimportant 

 except as the groundwork for selection to act on, in which 

 respect it is all important), I shall discuss under several heads, 

 but I can come, as you may well believe, only to very partial 

 and imperfect conclusions." 



It is, I think, of especial interest to find Darwin 

 at this early period arguing in a most convincing 

 manner for the creative power of natural selection. 

 The selective power becomes, by accumulation, of 

 such paramount importance in the process, as com- 

 pared with the variations, that, although these latter 

 are absolutely essential, man may be said to make 

 his domestic breeds and Nature her species. The 

 man who argued thus had been through and had 

 left behind the difficulty that, even now, is often 

 raised that "before anything can be selected it 

 must be," and therefore that selection is of small 

 account as compared with variation. 



