THE GROUSE SUBFAMILY 27 



are moulted, and in July, when the new white leg feathers are appear- 

 ing, the claws are shed. This shedding of the claws, which occurs also 

 in the red-grouse, is a curious phenomenon difficult to account for. 



Finally, it has been asserted that the "eclipse" dress of the 

 female red-grouse is assumed in part by a moult, and in part by a 

 repigmentation and a rearrangement of the pattern in the old 

 feathers of the " supernuptial " dress. There is absolutely not a 

 scrap of evidence, worthy of the name, in support of such a contention : 

 all that we know of the structure and development of the feather, 

 and of the physiological changes of the body generally, is in direct 

 conflict with such an assumption. 



We come now to the plumage-changes of the ptarmigan, which, 

 perforce, have been left till the last, since they are remarkable for the 

 fact that they moult no less than three times during the year. This 

 peculiarity, however, be it noted, is shared with the willow-grouse, a 

 species closely resembling the red -grouse, but differing in the 

 assumption of a white winter dress, and the white remiges and wing 

 coverts, and extensive area of white on the under parts. We may 

 probably, therefore, regard this white winter plumage as a livery 

 superimposed on the two normal plumages. The nuptial, or summer 

 plumage of the ptarmigan, it will be noticed, makes its appearance 

 during March and April, and by the end of May is complete. This 

 dress is worn till the end of July. In August the blue-grey dress 

 already described is assumed, and this is worn till the end of October 

 or well into November in mild seasons, when the white dress of 

 winter is assumed. 



That the three distinct liveries of the ptarmigan are all highly 

 protective in their coloration there can be no question: there are 

 few birds, indeed, which demonstrate the theory of protective 

 coloration better than the ptarmigan. On this more will be said 

 presently. 



What now remains to be said of the Grouse-tribe concerns the 

 history of their courtship and the care of the young: and the 



