Ornithological and Other Oddities 



editions of their parents — and if it were advan- 

 tageous for this strong and plucky bird to 

 resemble a bird of prey, no doubt these pre- 

 cociously-plumaged youngsters would be killed 

 off and only the barred ones survive, until the 

 barred young plumage was the only one found. 

 As this is not the case, we may assume no 

 mimicry is necessary. 



It should, however, be observed that there is 

 no gradation between the two forms, and so, if 

 the barred plumage became of mimetic value, it 

 would have done so without the gradual evolution 

 of a more and more marked resemblance insisted 

 on by entomological theorists on this fascinating 

 subject, but by the natural utilisation of a re- 

 semblance already existing; for a barred plumage 

 in young cuckoos is so very common that we may 

 fairly take it in the crow-pheasant as the normal 

 one, and the self-coloured young birds as more 

 recent offshoots, since there is a strong tendency 

 in birds for the young to drop their immature 

 plumage and assume at once that of the adult 

 when this can be done with safety. 



That, although a merely general resemblance 



is enough to make an impression, details would 



need to be added in some cases, is shown by the 



fact that where it is a matter of life or death to 



birds to know one similar species from another, 



they can distinguish them even where there is a 



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