The Making of Species 
garus ceruleus), also Indian ; but the resemblance 
extends to a structural detail which can hardly 
have mimetic value—namely, the harmless snake 
has long, fang-like front teeth, though these are 
unconnected with poison-glands. Animals which 
come into contact with the krait and its mimic 
are hardly likely to inspect their teeth. 
(4) A considerable number of birds of the 
shrike group—known as Cuckoo-Shrikes (Cam- 
pophaga) —closely resemble cuckoos in plum- 
age; but even if they derive any benefit from 
mimicking birds which are credited with being 
mimics already, they cannot profit by the fact 
that the shafts of the rump-feathers in both groups 
are stiffened ; this being a peculiarity which would 
not be perceptible until the bird was in the grasp 
of an aggressor. 
(c) As a third case of coincidence we may 
refer to the tubercle in the nostril of the Brain- 
fever-bird (zerococcyx varius), as a minute detail 
of hawk-like appearance, though not present in 
the particular species imitated. 
6. The argument that mimetic resemblances 
are producd in the most diverse ways, but the 
result is uniform, loses much of its force when 
we consider the various methods by which 
short-tailed birds appear to have long caudal 
appendages. 
In the peacock it is the upper tail coverts 
which are elongated; in the Stanley Crane 
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