Alfred Russel Wallace 



from their feeding-place by a caterpillar with large eye- 

 like spots on the broad anterior segments of the body. 

 Fritz Mttller has well discussed the first steps of mimicry 

 with butterflies, and comes to nearly or quite the same 

 conclusion as you, but supports it by additional argu- 

 ments. 



Fritz Mtiller also has lately shown that the males alone 

 of certain butterflies have odoriferous glands on their wings 

 (distinct from those which secrete matter disgusting to 

 birds), and where these glands are placed the scales assume 

 a different shape, making little tufts. 



Farewell : I hope that you find Dorking a pleasant place ?• 

 I was staying lately at Abinger Hall, and wished to come 

 over to see you, but driving tires me so much that my 

 courage failed. — Yours very sincerely, Chas. Dabv^in. 



Madeira Villas Madeira Road, Ventnor, Isle of Wight. 



September 3, 1877. 



My dear Darwin, — Many thanks for your letter. Of 

 course I did not expect my paper to have any effect on 

 your opinions. You have looked at all the facts so long 

 from your special point of view that it would require con- 

 clusive arguments to influence you, and these, from the 

 complex nature of the question, are probably not to be 

 had. We must, I think, leave the case in the hands of 

 others, and I am in hopes that my paper may call suffi- 

 cient attention to the subject to induce some of the great 

 school of Darwinians to take the question up and work it 

 out thoroughly. You have brought such a mass of facts 

 to support your view, and have argued it so fully, that I 

 hardly think it necessary for you to do more. Truth will 

 prevail, as you as well as I wish it to do. I will only make 

 one or two remarks. The word ^^ voluntary '' was inserted 

 in my proofs only^ in order to distinguish clearly between 



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