88 What Man does in Selection. 



species.&quot; This result is due to the accumulation 

 in one direction, during many generations, of 

 slight differences, differences that may be wholly 

 inappreciable to the uneducated eye and touch. 

 &quot; The key,&quot; says Darwin, &quot; is man s power of 

 accumulative selection ; nature gives successive 

 variations ; man adds them up in certain direc 

 tions useful to him. &quot; Kow, this mode of language 

 (of which I have hitherto availed myself) is not 

 capable of misinterpretation in relation to man ; 

 for everybody knows it is only by metaphor that 

 man can be said to have the power of accumulat 

 ing variations or adding them up. It is very 

 manifest that man can do nothing towards the re 

 sult except leave the varieties that please him fiee 

 to breed together. As it is nature that gives the 

 modifications, so it is nature that consolidates 

 them ; man s power is limited to selecting from 

 the materials given by nature that on which he 

 wishes her further to operate. But that simple 

 intervention does not explain the accumulation 

 any more than the origination of variations ; and, 

 for the rest, we have to confess that u the laws 

 governing inheritance are for the most part un 

 known.&quot; The breeder s conscious selection, then, 

 is not the cause, but at most the negative condi 

 tion, of the origin of domestic races. 



