18661872] SEXUAL SELECTION 



I hope that you will not think me an intolerable bore. It Letter 455 



is most improbable that you could get me an answer, but 



I ask on mere chance. Macacus silenus 1 has a great mane 



of hair round neck, and passing into large whiskers and 



beard. Now what I want most especially to know is whether 



these monkeys, when they fight in confinement (and I have 



seen it stated that they are sometimes kept in confinement), 



are protected from bites by this mane and beard. Any one 



who watched them fighting would, I think, be able to 



judge on this head. My object is to find out with various 



animals how far the mane is of any use, or a mere ornament. 



Is the male Macacus silenus furnished with longer hair than 



the female about the neck and face ? As I said, it is a 



hundred or a thousand to one against your finding out 



any one who has kept these monkeys in confinement. 



To F. Mullen Letter 456 



Down, August 28th [1870]. 



I have to thank you very sincerely for two letters : one of 

 April 25th, containing a very curious account of the structure 

 and morphology of Bonatea. I feel that it is quite a sin that 

 your letters should not all be published ! but, in truth, I have 

 no spare strength to undertake any extra work, which, though 

 slight, would follow from seeing your letters in English 

 through the press not but that you write almost as clearly 

 as any Englishman. This same letter also contained some 

 seeds for Mr. Farrer, which he was very glad to receive. 



Your second letter, of July 5th, was chiefly devoted to 

 mimicry in lepidoptera : many of your remarks seem to me 

 so good, that I have forwarded your letter to Mr. Bates ; but 

 he is out of London having his summer holiday, and I have 

 not yet heard from him. Your remark about imitators and 

 imitated being of such different sizes, and the lower surface 

 of the wings not being altered in colour, strike me as the most 

 curious points. I should not be at all surprised if your sug- 

 gestion about sexual selection were to prove true ; but it 

 seems rather too speculative to be introduced in my book, 

 more especially as my book is already far too speculative. 

 The very same difficulty about brightly coloured caterpillars 



1 Macacus silenus L., an Indian ape. 



