1670.] SEDGWICK. 305 



Again, can you give me reasons for believing that the 

 moderate differences between the female pheasant, the female 

 Gallus bankiva, the female black grouse, the pea-hen, the 

 female partridge, [and their respective males,] have all special 

 references to protection under slightly different conditions ? 

 I, of course, admit that they are all protected by dull colours, 

 derived, as I think, from some dull-ground progenitor ; and I 

 account partly for their difference by partial transference of 

 colour from the male and by other means too long to speci- 

 fy ; but I earnestly 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 

 makes me constantly distrust myself. I fear we shall never 

 quite understand each other. I value the cases of bright- 

 coloured, incubating male fishes, and brilliant female butter- 

 flies, solely as showing that one sex may be made brilliant 

 without any necessary transference of beauty to the other sex ; 

 for in these cases I cannot suppose that beauty in the other 

 sex was checked by selection. 



I fear this letter will trouble you to read it. A very short 

 answer about your belief in regard to the ? finches and gal- 

 linaceae would suffice. 



Believe me, my dear Wallace, 



Yours very sincerely, 



CH. DARWIN. 



C. Darwin to J. D. Hooker. 



Down, May 25 [1870]. 



. . . , Last Friday we all went to the Bull Hotel at 

 Cambridge to see the boys, and for a little rest and enjoy- 

 ment. The backs of the Colleges are simply paradisaical. On 

 Monday I saw Sedgwick, who was most cordial and kind ; in 

 the morning I thought his brain was enfeebled ; in the evening 

 he was brilliant and quite himself. His affection and kind- 

 ness charmed us all. My visit to him was in one way un- 

 fortunate ; for after a long sit he proposed to take me to the 

 museum, and I could not refuse, and in consequence he utterly 



