272 Darwin, and after Darwin. 



peacocks. But to say that it is due to correlation 

 with general "vitality/' is merely to discharge the 

 doctrine of correlation of any assignable meaning. 

 Vitality, or " perfect adaptation to the conditions of 

 existence," is obviously a prime condition to the 

 occurrence of a peacock's tail, as it is to the occur- 

 rence of a peacock itself ; but this is quite a different 

 thing from saying that the specific characters which 

 are presented by a peacock's tail, although useless 

 in themselves are correlated with some other and 

 useful specific characters of the same bird as we saw 

 in a previous chapter with reference to secondary 

 sexual characters in general. Therefore, when Mr. 

 Wallace comes to the obvious question why it is that 

 even in " allied species," which must be in equally 

 " perfect adaptation to the conditions of existence,'' 

 there are no such " wonderful superfluities of plumage," 

 he falls back as he previously fell back on what- 

 ever unknown causes it may have been which pro- 

 duced the peacock's tail, when the primary condition 

 to their operation has been furnished by " complete 

 success in the battle for life." 



I have quoted the above passages, not so much for 

 the sake of exposing fundamental inconsistencies on 

 the part of an adversary, as for the sake of observing 

 that they constitute a much truer exposition of 

 " Darwinism " than do the contradictory views ex- 

 pressed in some other parts of the work bearing that 

 title. For even if characters of so much size and elabo- 

 ration as the tail of a peacock, the plumes of a bird of 

 paradise &c., are admitted to be due to non-utilitarian 

 causes, much more must innumerable other characters 

 of incomparably less size and elaboration be mere 



