The Wallace-Darwin Correspondence 



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 specify; 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 

 ralue the cases of bright-coloured, incubating male fishes 

 — and brilliant female butterflies, 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 Gallinaceae would suffice. — Believe me, my dear Wallace, 

 yours very sincerely, Ch. Darwin. 



9 St. Mark's Crescent, N.W. September 27, 1868. 



Dear Darwin, — Your view seems to be that variations 

 occurring in one sex are transmitted either to that sex ex- 

 clusively or to both sexes equally, or more rarely partially 

 transferred. But we have every gradation of sexual colours 

 from total dissimilarity to perfect identity. If this is ex- 

 plained solely by the laws of inheritance, then the colours 

 of one or other sex will be always (in relation to their 

 environment) a matter of oliance. I cannot think this. I 

 think Selection more powerful than laws of inheritance, 

 of which it makes use, as shown by cases of two, three or 

 four forms of female butterflies, all of which have, I have 

 little doubt, been specialised for protection. 



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