WHEATEARS, DABCHICKS 77 



therefore, that such violent movements as are here 

 imagined might have this effect, and thus, though 

 excited originally by rage or some high state of 

 emotion only, might be persisted in and increased 

 through experience of their efficacy. But if this 

 does ever happen, may we not have here the origin 

 or one of the origins of those undoubted displays 

 made by the male bird to the female, on which the 

 theory of sexual selection is chiefly based? That 

 the male birds should, in the beginning, have con- 

 sciously displayed their plumage, in however slight 

 a manner, to the females, with an idea of it striking 

 them, seems improbable, and, even if we might 

 assume the intelligence requisite for this, the theory 

 of sexual selection supposes the beauty of the plumage 

 to have been gained by the display of it, not that 

 the display has been founded upon the beauty. Then 

 what should first lead a bird of dull plumage con- 

 sciously to display this plumage before the female? 

 A mere habit of the male, increased and perfected 

 by the selective agency of the female (as this is ex- 

 plained by Darwin), has hitherto as far as I know 

 been considered a sufficient explanation of the 

 origin and early stages of such displays as are 

 now made by the great bustard, the various birds 

 of paradise, or the argus pheasant. But if we can 

 show a likelihood as to how this habit has arisen 

 we are, at least, a step farther forward, even if a 

 slight difficulty has not thereby been removed. 



Now, with regard to these wheatears, it will, I 

 think, be admitted that the little frenzies of the 

 male birds as I have described them were of a 

 very marked, and, indeed, extraordinary nature, and 



