CHAP. X.] SEXUAL SELECTION. 321 



insects ?&quot; We may also add, the colours and ornaments of 

 all other animals also, including birds ? 



There is, however, another reason determining Mr. Darwin 

 to accept sexual selection ; and it is probably this Mr Danvin 

 which, in his mind, mainly gives importance to the f fl , u ; &quot;?? d by 

 facts mentioned as to the plumage and motions of views - 

 birds. He says of &quot; display,&quot; &quot; It is incredible that all this 

 display should be purposeless &quot; (vol. ii. p. 399) ; and again 

 (vol. ii. p. 93), he declares that any one who denies that the 

 female Argus pheasant can appreciate the refined beauty of 

 the plumage of her mate, &quot;will be compelled to admit that 

 the extraordinary attitudes assumed by the male during the 

 act of courtship, by which the wonderful beauty of his 

 plumage is fully displayed, are purposeless ; and this is a 

 conclusion which I for one will never admit.&quot; It seems then 

 that it is this imaginary necessity of attributing purposeless- 

 ness to acts which determines him to attribute that peculiar 

 and special purpose to birds actions which he does attribute 

 to them. But surely this difficulty is a mere chimaera. Let 

 it be granted that the female does not select; yet the 

 display of the male may be useful in supplying the necessary 

 degree of stimulation to her nervous system, and to that of 

 the male. As Mr. Darwin says (p. 275), the lion enraged 

 &quot;tries to make himself as terrible as possible.&quot; But he 

 does not know that he is, and therefore does not intend 

 to be terrible. Is not this a parallel case to the display 

 of male pheasants? Pleasurable sensation, perhaps very 

 keen in intensity, may thence result to both. There 

 would be no difficulty in suggesting yet other purposes 

 if we were to ascend into higher speculative regions. Mr. 

 Darwin gives us in one p^ace a very remarkable passage; 

 he says : 



&quot;With respect to female birds feeling a preference for particular 

 males, we must bear in miad that we can judge of choice A n iimstra- 

 being exerted only by placing ourselves in imagination li&amp;lt;m - 

 in the same position. If an inhabitant of another planet were to 

 behold a number of young rustics at a fair, courting and quarrelling 



V 



