96 ARE THE EFFECTS OF USE INHERITED f 



must be subjected to changed habits for any 

 appreciable result." 1 What does this mean ? 

 One of two things. Either the tendency is 

 very weak, or it is non-existent. If it is so 

 weak that we cannot detect its alleged effects 

 till several generations have elapsed, during which 

 time the more powerful agency of selection has 

 been at work, how are we to distinguish the effects 

 of the minor factor from that of the major ? Are 

 we to conclude that use-inheritance plus selection 

 will modify races, just as Voltaire firmly held that 

 incantations, together with sufficient arsenic, would 

 destroy flocks of sheep ? Is it not a significant 

 fact that the alleged instances of use-inheritance 

 so often prove to be self-conflicting in their 

 details ? 



For satisfactory proof of the prevalence of a 

 law of use-inheritance we require normal instances 



1 Variation of Animals and Plants under Domestication, ti. 

 287-289. 



