152 Permanence and Evolution. 



when his attention has once been called to it, 

 that of slightly different strains of organised life, 

 the one which has any trifling advantage is 

 likely to prevail over the other in the long run ; 

 but nothing can be inferred from this, unless it 

 is conjoined with the notion of unlimited varia- 

 bility, while, contrariwise, natural selection being 

 certain, any facts which lead to the opinion that 

 organised forms are not as the unconditional 

 workings of natural selection, coupled with 

 spontaneous variability, would have made them, 

 throw doubt, not on natural selection, but on 

 the variability of living types. 



What are the characters which conduce to 

 success in the struggle for life ? As I have 

 elsewhere said, hardiness, omnivorousness, and 

 fertility, much more than any complicated special 

 adaptations witness the rabbit ; these characters 

 are also what evolutionists call highly variable, 

 being very different in closely allied forms. Why, 

 then, has natural selection not stamped these 



