The Making of Species 
preyed upon by birds, but have to fear chiefly 
the comparatively dull-eyed lizards and mammals, 
of which the latter hunt mainly by scent. As 
a matter of fact, the most striking cases of 
resemblance to inanimate objects are seen among 
butterflies, which seem to stand least in need of 
them. 
We have already cited the case of the butterfly 
Precis artexia. Even more marked does the 
unnecessary elaboration of the likeness seem to 
be in the Kallima butterflies. 
Tue TueEory or WARNING COLOURATION 
All biologists admit that there exist some 
organisms which are not coloured so as to be 
inconspicuous. Indeed, the colouring of certain 
species is such as to render them particularly 
conspicuous. Such species are said to be warn- 
ingly coloured. They are supposed to be 
inedible, or to have powerful stings or other 
weapons of defence, or to resemble in appear- 
ance organisms which are thus protected. In 
the first two cases they are said to be warningly 
coloured, and in the last they are cited as 
examples of protective mimicry. With the 
theory of mimicry we shall deal shortly. We 
must first discuss the hypothesis of warning 
colouration. 
When animals are unpalatable, or when they 
possess a sting or poison-fangs, it is, to use the 
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