GROUSE AND PTARMIGAN. 



397 



shown in the accompanying cut. ' The most curious bird of the group is, however, 

 the red grouse (i. scoticus), peculiar to the British Islands, in which the changes 

 of plumage appear unique ; this species differing from all the others in having no 

 white winter plumage, and the flight - feathers being always brownish black. 

 Subject to enormous variation in plumage, the extreme diverseness may be 

 enumerated as the black, 



red, and white spotted .^ .,^,^,^ „ 



phases. The first form 

 has the entire plumage 

 black, and is by far the 

 rarest ; the second, in 

 which the general colour 

 is rufous chestnut, is 

 chiefly met with in the 

 west coast of Scotland, 

 the outer Hebrides and 

 Ireland; while the white- 

 spotted variety, in which 

 all the feathers of the 

 breast and under-parts, 

 and sometimes also those 

 of the head and back, 

 are widely tipped with 

 white, is apparently 

 dependent on latitude 

 and altitude. 



The 

 nearest ally 

 of the red grouse is the 

 circumpolar ripa or 

 willow-grouse {L. albus), 

 which has three distinct 

 .seasonal plumages, those 

 of summer and autumn 

 (shown in the accom- 

 panying cut), closely resembling those of the red grouse, while the winter dress 

 is white, and the bird can then only be distinguished by its large size and thick 

 bill. That the red grouse is only an insular form of the willow-grouse there can 

 be little doubt, and it has in all probability gradually ceased to assume a white 

 winter dress, which in a milder climate was no longer essential for its protection. 

 Under these circumstances it might be inferred that in the red grouse there 

 would be only two changes of plumage, namely, in summer and autumn, but this, 

 for some at present unknown cause, is only the case with the female. In early 

 spring the latter begins to assume the summer dress of black mottled and barred 

 with bufl" or rufous buff", which harmonises so well with the surroundings of her 

 nest that she is comparatively safe from detection. In the end of June she casts 



Willow-Grouse. 



SPITZBERGEN PTARMIGAN. 



