The Making of Species 
the enemies are certainly sharp-sighted and 
successful in pursuit, but that perfection in detail 
makes their task a harder one, and gives to the 
individuals possessing it in a higher degree than 
others, increased chances of escape, and of be- 
coming the parents of future generations.” 
(Essays on Evolution, p. 302.) 
This long quotation requires careful considera- 
tion, since to us it appears to be typical of the 
kind of reasoning resorted to by Neo-Darwinians. 
Note the reference to our ‘imperfect know- 
ledge of the struggle for existence.” This is 
almost invariably the last refuge of the Neo- 
Darwinian when worsted in argument. We 
fully admit that there is still much to be learned 
of the nature of the struggle for existence, but 
such a statement sounds very curious when 
uttered to those who pin their faith to the theory 
which sees in the principle of natural selection 
an explanation of all the phenomena of the or- 
ganic world. Natural selection, be it remembered, 
is but a name for the struggle for existence. 
“Birds,” says Professor Poulton, ‘“‘are the 
chief enemies of insects.” This may be so. 
But we greatly doubt whether they are the 
chief enemies of butterflies and moths, among 
which the most perfect examples of mimicry are 
supposed to occur. 
We have watched birds closely for some years, 
but believe that we could almost count on our 
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