i866— 1872] SEXUAL SELECTION 59 



dye with mag nta a pigeon or two. 1 Would it not be better Letter 428 

 to dye the tail alone and crown of head, so as not to make 

 too great difference? I shall be very curious to hear how 

 an entirely crimson pigeon will be received by the others 

 as well as his mate. 



I'.S. — Perhaps the best experiment, for my purpose, would 

 be to colour a young unpaired male and turn him with other 

 pigeons, and observe whether he was longer or quicker than 

 usual in mating. 



To A. R. Wallace. Letter 429 



Down, April 29th [1867]. 



I have been greatly interested by your letter, 2 but your 

 view is not new to me. If you will look at p. 240 of the 

 fourth edition of the Origin you will find it very briefly given 

 with two extreme examples of the peacock and black grouse. 

 A more general statement is given at p. 101, or at p. 89 

 of the first edition, for I have long entertained this view, 

 though I have never had space to develop it. But I had 

 not sufficient knowledge to generalise a- far as you do 

 about coh airing and nesting. In your paper perhaps you 

 will just allude to my scanty remark in the fourth edition, 

 because in my Essay on Man I intend to discuss the whole 

 subject of sexual selection, explaining as I believe it does 

 much with respect to man. 1 have collected all my old 

 notes, and partly written my discussion, and it would be 

 flat work for me to give the leading idea as exclusively 



1 " Mr. Tegetmeier, at my request, stained some of his birds with 

 magenta, but they were not much noticed by the others." — Descent of 

 Man (1901), p. 637. 



' We have not been able to find Mr. Wallace's letter to which this 

 is a reply. It evidently refers to Mr. Wallaces belief in the paramount 

 importance of protection in the evolution of colour. This is clear from 

 the P.S. to the present letter and from the passages in the On 

 referred to. The first reference, Ed. iv., p. 240, is as follows : 

 " We can sometimes plainly see the proximate cause of the trans- 

 mission of ornaments to the males alone ; for a pea-hen with the 

 long tail of the male bird would be badly fitted to sit on her eggs, 

 and a coal-black female capercailzie would be far more conspicuous on 

 her nest, and more exposed to danger, than in her present modest 

 attire." The passages in Ed. I. (pp. 89, ion do not directly bear on 

 the question of protection. 



