BIRDS OF THE MOORLAND 321 



The Ptarmigan — the smallest of the British 

 Grouse — is found in Great Britain only on the 

 summits of the loftiest Scotch mountains, princi- 

 pally in Ross and Sutherland. Here its delicately 

 pencilled grey and white plumage blends so com- 

 pletely with the lichen-covered rocks and mossy 

 boulders amidst which it lives, that it is well-nigh 

 indistinguishable from them even at a few yards' 

 distance. 



This species is interesting by reason of its 

 gradual change in colouring as the seasons 

 advance, the new feathers, at every stage, falling 

 into perfect correspondence with the changing hues 

 of the rock and hill, until at length, the grey 

 pencillings merge into pure white in completest 

 harmony with the snow-covered summits. 



The Blackcock is the nearest akin to the Red 

 Grouse, but it differs from it in many of its habits. 

 In the first place, in common with the Capercaillie, 

 it is polygamous. In the pairing season the males 

 assemble before daybreak to utter a succession of 

 loud notes, which call the females together. At 

 these gatherings the cocks move to and fro with 

 trailing wings and outspread tails, performing 

 extraordinary antics, and the fiercest battles ensue, 

 each victor at length withdrawing, accompanied by 

 his following of hens. 



Again, differing from the Red Grouse, the Black- 

 cock is not strictly a moorland bird. Although 

 cover is not essential to its well-being, it usually 

 resorts to swampy, rush-grown places where 

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