False Batesian Mimicry 
In Africa there is a tit (Parus leucopterus) 
which has the same very unusual colouration as 
an East-Indian bulbul (M/tcropus melanoleucus), 
both being black with a white patch on the wing- 
coverts. These two birds are about the same 
size. As showing the purely coincidental char- 
acter of such resemblances, we may mention that 
this same rare pattern occurs again in our Black 
Guillemot (Uva grylle) and in the Muscovy Duck 
(Cazrina moschata). 
We have already quoted Gadow (p. 198) on 
“false mimicry” among snakes. He also gives, 
on p. 110 0f Through Southern Mexico, an example 
of this phenomenon among amphibia. It is, he 
writes, “impossible to distinguish certain green 
tree-frogs of the African genus Rafpza from a 
FTyla, unless we cut them open. If they lived 
side by side, which they do not, this close resem- 
blance would be extolled as an example of 
mimicry.” 
We should be very greatly surprised if abun- 
dant examples of “false mimicry” are not found 
among insects. We trust that this remark will 
stimulate some entomologist to pay attention to 
the subject. 
It is the essence of Miillerian mimicry that 
both model and copy are immune from attack 
from enemies. Unfortunately for the theory, 
similar resemblances occur among birds of prey, 
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