THE COMMON PTARMIGAN* 
151 
litary pairs remain on Skit! daw, or some of its preci- 
pitous neighbours, the range of the Grampians will 
he its most southern British station- Another bird 
has lately been found lit thin country, which was be- 
fore thought to be an inhabitant of America only, 
the L ago pus rupestris or Iloek Ptarmigan. From its 
close resemblance in plumage, it has been confounded 
with the common ptarmigan ; but one or two spe- 
cimens have lately been got in the more northern 
Highland districts. In both birds ihe plumage is of 
the most unsullied white during winter. In summer 
they are mottled with tbits of black; in the first min- 
gled with grey and yellow, in the second with yel- 
low alone. The size varies also, the last being about 
two inches less than the Common Ptarmigan, The 
chief distinctions to he seized upon at first sight, are 
the less size, and the black feathers of the back be- 
ing cut into upon the edges, with patches of yellow 
only, contrasted with the larger size and grey plumage 
of the other. 
They inhabit the most barren and rocky spots, 
often where nothing is to he seen hut an intermin- 
able series of rugged rocks distributed in boulder 
masses, varying in size, from huge lumps to pieces 
of a few inches in diameter. Here, during spring 
and summer, the pairs and their broods remain 
the only inhabitants, and are discovered with tho 
greatest difficulty, the mixture of the colours of tho 
plumage forming a tint which harmonizes with that 
of the grey rocks around. At this season they are 
also tame and familiar, running before the intruder, 
and uttering their peculiarly low wild call, which i# 
