BLACKCOCK. 193 



which they skulk. They are thus enabled to 

 escape the notice of their natural enemies, 

 the birds of prey, from whose ravages they 

 suffer far more in a state of nature than from 

 any other cause. We may take the ptarmi- 

 gans as the most typical example of this 

 class of birds ; for in summer their zigzagged 

 black-and-brown attire harmonises admirably 

 wLh the patches of faded heath and soil 

 upon the mountain-side, as every sportsman 

 well knows ; while in the winter their pure 

 white plumage can scarcely be distinguished 

 from the snow in which they lie huddled and 

 crouching during the colder months. Even 

 in the brilliant species, Mr. Darwin and Mr. 

 Wallace have pointed out that the orna- 

 mental colours and crest are never handed 

 down to female descendants when the habits 

 of nesting are such that the mothers would 

 be exposed to danger by their conspicuous- 

 ness during incubation. Speaking broadly, 

 only those female birds which build in hollow 

 trees or make covered nests have bright hues 



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