398 GAME-BIRDS. 
the whole of her plumage, and by the beginning of September the change to the 
dark buff-spotted autumn dress is complete, though in some examples, probably 
birds of the year, a few feathers of the back may still be seen in quill as late as 
December. The male, on the other hand, makes no spring change, not a single 
feather being renewed between January and the end of June; but after the 
breeding-season the entire plumage is replaced by the autumn feathers, which are 
black, marked, barred, and often edged round the margin with buff. Thus, while 
at the end of August the cock bears a considerable resemblance to the female in 







WILLOW-GROUSE IN SUMMER DRESS (3 nat. size). 
May, though the buff markings are never so coarse, no sooner is the autumn 
plumage donned than the dark chestnut winter feathers, with their mottled black 
bars, begin to appear, the whole change being completed by December. Some of 
the autumn feathers are, however, often retained on the back, and may be distin- 
guished from the winter plumage at a glance. The male breeds in this plumage, 
and very shabby and worn he is by the end of the nesting-season. It will thus 
be seen that the male and female have two changes in the season, but while 
those of the latter are, as might be expected, made in spring and autumn, the 
male changes in autumn and winter. The Rocky Mountain ptarmigan (L. 
lewewrus) is the smallest representative of the genus, and is recognised by its 
pure white tail. 
