Permanence and Evolution. 139 



till in course of time dull colouring and the 

 preference for it would be established throughout 

 the animal kingdom. 



But there are many evolutionists who are 

 not strict Darwinians, none of whom have at- 

 tempted to give their views the same systematic 

 distinctness as Darwin has to his. But before 

 considering this subject it will be well to say a 

 few more words on sexual selection, by which 

 the lacunse in the hypothesis of natural selection 

 are attempted to be filled up. The hypothesis 

 rests on these alleged facts : 



That the law of battle prevails extensively in 

 nature ; also (which last is what is principally 

 meant by sexual selection) that female animals 

 exercise an extensive power of choice among 

 males ; that they select such as exhibit slight 

 variations in plumage, etc., which happen to be 

 attractive to them, who therefore have a better 

 chance of leaving offspring than others, and that 

 this is the origin of the complicated and brilliant 



