wo | Dwicut, Moult of Quails and Grouse. 159 
have been shown by the specimens described. Adults become 
wholly white, the females indistinguishable from young birds, but 
‘males apparently assume crown feathers which are basally black, 
gray prevailing in young birds. An Alaska specimen (Amer. 
Mus. No. 26180, ¢, October), indicates that the white dress may 
be acquired before November in that latitude; and this bird as 
well as others (e. g., Amer. Mus. No. 26165, ¢, Labrador, De- 
cember 20) show that basally black crown feathers grow in the 
autumn and are not white ones recolored in the spring. 
Second or Adult Nuptial Plumage.—This is acquired, as in the 
young bird, by a partial prenuptial moult, doubtless extremely 
limited in high latitudes. The colors of adults are somewhat 
richer with a tendency to less barring and finer mottlings, at least 
in males. Two males (Amer. Mus. No. 49902, Great Slave Lake, 
Canada, June, and No. 26890, Archangel, Russia, May 5) illus- 
trate new growth of feathers radiating from the usual points, the 
late renewal of the forehead and lores being excellently shown. 
The growth is confined wholly to the head, the rest of the bird 
being pure white. Numerous other specimens examined need 
not be here described, although illustrating the varying extent 
of the prenuptial renewal. 
Later plumages and moults are but repetitions of those already 
fully explained in all details. 
The wear of feathers in the Ptarmigans throws some light upon 
questions of plumage but they do not appear to suffer much from 
it and the rapid succession of the summer moult prevents marked 
abrasion or fading in most cases. As for the moult of the claws 
described by several observers, I need not discuss it in the present 
connection. 
That the plumages are complicated and difficult to understand 
I am ready to admit, but I fail to find the slightest reason for sup- 
posing them to be produced otherwise than by moult. I may not 
have systematized the plumages or the moults in the best manner, 
but at least I have tried to bring out the facts in a way that I 
hope may clear up the misty ideas that have prevailed in spite of 
the plumages of the Ptarmigans having been the theme of so 
many writers. 
