264 THE PRINCIPLES OF [Part II. 



ent in the one sex and absent in the other, or when, as is 

 frequently the case, they are more highly developed in the 

 one than the other, it is almost invariably the male, as far 

 as I can discover, which retains such organs, or has them 

 most devoloped ; and this shows that the male is the more 

 active member in the courtship of the sexes. 12 



The female, on the other hand, with the rarest excep- 

 tion, is less easier than the male. As the illustrious Hun- 

 ter 13 long ago observed, she generally " requires to be 

 courted ; " she is coy, and may often be seen endeavoring 

 for a long time to escape from the male. Every one who 

 has attended to the habits of animals will be able to call 

 to mind instances of this kind. Judging from various 

 facts, hereafter to be given, and from the results which 

 may fairly be attributed to sexual selection, the female, 

 though, comparatively passive, generally exerts some 

 choice and accepts one male in preference to others. Or 

 she may accept, as appearances would sometimes lead us 

 to believe, not the male which is the most attractive to 

 her, but the one which is the least distasteful. The ex- 

 ertion of some choice on the part of the female seems 

 almost as general a law as the eagerness of the male. 



We are naturally led to inquire why the male in so 

 many and such widely-distinct classes has been rendered 

 more eager than the female, so that he searches for her 

 and plays the more active part in courtship. It would be 



12 One parasitic Hymenopterous insect (Westwood, ' Modern Class, 

 of Insects,' vol. ii. p. 160) forms an exception to the rule, as the male 

 baa rudimentary wings, and never quits the cell in which it is born, 

 while the female has well-developed wings. Audouin believes that the 

 females are impregnated by the males which are born in the same cells 

 with them ; but it is much more probable that the females visit other 

 cells, and thus avoid close interbreeding. We shall hereafter meet with 

 a few exceptional cases, in various classes, in which the female, instead 

 of the male, is the seeker and wooer. 



13 \ Essays and Observations,' edited by Owen, vol. i. 1861, p. 194. 



