GROUSE AND PTARMIGAN. 
397 
shown in th& accompanying cut. The most curious bird of the group is, however, 
the red grouse ( L. 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 
Willow-Grouse. 
nearest ally 
SPITZBERGEN PTARMIGAN. 
of the red grouse is the 
circumpolar ripa or 
willow-grouse ( L . albus), 
which has three distinct 
seasonal plumages, those 
of summer and autumn 
(show r n 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 buff 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 
