[866 1873] SEXUAL SELEi I I « > N 



appearing on the head of a male bird, and which arc at first Letter 449 

 transmitted to both sexes, would come to be transmitt d 

 to males alone. It is not enough that females should 

 produced from the males with red feathers, which should 

 be destitute of red feathers; but these females must have a 

 latent tendency to produce such feathers, otherwise th 

 would cause deterioration in the red head-feathers of their 

 male offspring. Such latent tendency would be shown by 

 their producing the red feathers when old, or diseased in their 

 ovaria. But I have no difficulty in making the whole head 

 red if the few red feathers in the male from the first tended 

 to be sexually transmitted. I am quite willing to admit that 

 the female may have been modified, either at the same time 

 or subsequently, for protection by the accumulation of varia- 

 tions limited in their transmission to the female sex. I 

 to your writings the consideration of this latter point. But 1 

 cannot yet persuade myself that females alone have often 

 been modified for protection. Should you grudge the trouble 

 brieily to tell me, whether you believe that the plainer head 

 and less bright colours of female ch iffinch, the less red on th 

 head and less clean colours of female goldfinch, the much le 

 red on the breast of the female bullfinch, the paler crest of 

 golden-crested wren, etc., have been acquired by them for 

 protection? I cannot think so, any more than I can t ! 

 the considerable differences between fern de and male house- 

 sparrow, or much greater brightness of male Pa 

 (both of which build under cover) than of female Par:. 

 related to proteccion. I even misdoubt much whether the 

 less blackness of female blackbird is for 



Again, can you give me reasons for be'.' the 



moderate differences between the female pheasant, the lie 



Gallus b< 1, the female of black grouse, ti the 



female partridge, have all special referen :ction 



under slightly different conditions? I, of cou Imit that 



they are all protected by dull colours, deri\ I think, 



from some dull-ground progenitor ; and 1 account partly I 

 their difference by partial transference of colour t lie 



male, and by other means too long to specify ; but I e '■>' 



wish to .see reason to believe that each is specially adapted 

 for concealment to its environment. 



I grieve to differ from you, and it actually terrifies me and 



