194 THE COURTSHIP OF ANIMALS 



Mr. David Sharp, " is a large, sombre creature of black, 

 white and grey colours, but the male is brilliant with gold 

 and green, and is made additionally remarkable by a long 

 tail of unusual form on each wing." But a glance at the 

 two sexes will show that the female, though less 

 gorgeously arrayed, still disports a livery which is 

 of a highly specialized or elaborated character. How 

 are we to account for her differences in shape, size 

 and coloration on the older interpretation of Sexual 

 Selection ? The perceptual powers, the mentality, of a 

 Butterfly are surely of a far lower grade than those of a 

 bird, or even a fish. Here, therefore, we cannot attribute 

 the same possibilities of response to form and colour which 

 we can ascribe with tolerable safety to the vertebrates. 

 Yet the Sexual Selection theory as generally understood 

 demands this. 



So far so good. And now as to the part played by 

 Sexual Selection among the Lepidoptera. Darwin, in 

 formulating this, found its application to the Lepidoptera 

 a very disconcerting problem, being naturally disposed 

 to regard the extraordinary wealth of colour which these 

 insects exhibit as the outcome of a process of female 

 selection, in every way comparable to that which he held 

 to obtain among the birds. He did not postulate a con- 

 scious, deliberate, selection ; but a final abandonment 

 on the part of the female to the male which, by his beauty 

 and demonstrativeness, pleased her most. He assumed 

 that at this critical time she would always be surrounded 

 by rival suitors, offering varying if slight degrees of 

 difference : and, indeed, in many cases she is thus sur- 

 rounded. He remarks, in discussing the case of Butter- 

 flies : " The males sometimes fight together in rivalry, and 

 many may be seen pursuing or crowding round the same 



