The Making of Species 



garus cceruleus), 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. 



(6) 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 {Hierococcyx 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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