218 THE COLOURS OF ANIMALS 



life,' he writes. ' I am rejoiced that I passed over the 

 whole subject in the " Origin," for I should have made 

 a precious mess of it. You have most clearly stated 

 and solved a most wonderful problem. Your paper 

 is too good to be largely appreciated by the mob of 

 naturalists without souls ; but rely on it that it will 

 have lasting value, and I cordially congratulate you 

 on your first great work.' * This was Darwin's opinion 

 of a theory which is often lightly criticised or even con- 

 demned by many biologists who offer nothing in its 

 place. 



The relation of the theory of Mimicry to Evolution 



Mr. Bates's paper afforded a twofold support to the 

 arguments in the ' Origin of Species,' at a very criti- 

 cal time in the history of these opinions. In the 

 first place it showed that an important class of facts 

 was unintelligible upon any theory except that of 

 evolution. The proof of this is best given in Dar- 

 win's own words, also quoted by Mr. Francis Darwin. 2 

 'By what means, it may be asked, have so many 

 butterflies of the Amazonian region acquired then- 

 deceptive dress ? Most naturalists will answer that 

 they were thus clothed from the hour of their creation 

 an answer which will generally be so far triumph- 

 ant that it can be met only by long-drawn argu- 

 ments ; but it is made at the expense of putting an 



1 Life and Letters, vol. ii. pp. 391-93. 

 1 Ibid., vol ii. pp. 391-92. 



