PROTECTIVE AND AGGRESSIVE MIMICRY 253 



a different order, 1 which mimicked the ant, together 

 with its leafy burden. The piece of leaf was imitated 

 by a thin, flat expansion, and the resemblance was so 

 striking that Mr. Sclater's servant, who was a keen 

 observer, actually believed that he was looking at an 

 ant carrying its piece of leaf. 



Such cases can be explained by the operation of 

 natural selection 



This last example is, as far as I am aware, unique 

 in the detail with which the original is reproduced ; 

 not only is the specially protected species copied, but 

 it is depicted at its usual occupation, and the material 

 upon which it labours is also included in the picture. 

 I quote below a passage from Mr. Belt's work, be- 

 cause it expresses in the clearest and simplest way 

 what I believe to be a complete reply to those who 

 would urge the incompetence of natural selection to 

 produce so faithful and detailed a likeness. 



' The extraordinary perfection of these mimetic 

 resemblances is most wonderful. I have heard this 

 urged as a reason for believing that they could not 

 have been produced by natural selection, because a 

 much less degree of resemblance would have protected 

 the mimetic species. To this it may be answered that 

 natural selection not only tends to pick out and pre- 

 serve the forms that have Protective Eesemblances, 



1 Professor Westwood and Mr. W. F. Kirby believe that the insect 

 was one of the MembracidcB (Homoptera). 



