ANNALS 



OF 



The Entomological Society of America 



Volume II DECEMBER, 19 09 Number 4 



MIMICRY IN THE BUTTERFLIES OF NORTH AMERICA. 



B}- Professor E. B. Poulton, Oxford, England. 



Written from the notes of the Anniversary Address deHvered to the Entomolog- 

 ical Society of America, Baltimore, Thursday, December 31, 1908. 



Introductory. 



Within a few weeks of the hundredth anniversary of Darwin's 

 birth, and nearly midway between the fiftieth anniversaries of the 

 pubhcation of Natural Selection on July i last and the Origin of 

 Species on Nov. 24 next, it seemed to me specially appropriate 

 to select for this address a subject that is closely associated with 

 Darwinian teachings. Although he did not publish it during his 

 lifetime, we now know from his correspondence that Darwin 

 independently originated the interpretation of Mimicry which 

 was afterwards suggested by H. W. Bates. Its development in 

 the mind of the naturalist of the amazons and the rival theory 

 afterwards suggested by Fritz Mliller were both of them the direct 

 outcome, in Bates's case the very speedy outcome, of the Origin. 

 The deep interest which Darwin took in the hypotheses of both 

 naturalists is proved by mam^ a letter in his published cor- 

 respondence. All this forms a peculiarly fascinating chapter of 

 ancient histor^^ — nevertheless ancient history ; but if we desire to 

 choose a subject because of the light it can throw today and is 

 certain to throw tomorrow upon evolution and its causes, there is 

 no study which for promise -as well as performance can be set on 

 a higher level than Mimicry. 



In the course of the following address the word "Mimicry" 

 will be used with the restricted meaning attached to it by A. R. 

 Wallace. It will be applied solely to the superficial resemblances 

 between animals, and not to their likeness to vegetable or mineral 

 surroundings for the purpose of concealment. 



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