Theory of Mimicry Criticised 
display more than double this number of colours, 
we may draw attention to the fact that those 
birds which are most immune from attack are 
precisely those which display the smallest range 
as regards colour, e,g., hawks, owls, crows, gulls, 
storks, and cranes. As we have already sub- 
mitted, no question of Miillerian association 
comes in here. 
On the other hand, the eminently edible 
families of game-birds and ducks display great 
variety of colour, in the males at all events. 
4. As regards the statement that although 
in many cases the mimetic resemblances extend 
to the minutest detail, they are not accompanied 
by any structural changes except such as assist 
in the production of a superficial likeness, we may 
refer to the case we have already cited of the 
New Zealand cuckoo, which, though it so closely 
copies an American hawk, is typically cuculine in 
structure. Here, of course, there can be no 
question of advantage to the ‘ mimicking” 
cuckoo in the resemblances. 
5. In answer to the argument that mimetic 
resemblance extends to form, attitude, and move- 
ment, as well as colour, and that deep-seated 
organs are affected only when the superficial 
resemblance is thereby intensified, we may draw 
attention to such cases as the following :— 
(2) The harmless Indian Snake(Zycodon aulicus) 
is closely similar to the well-known Krait (Bun- 
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