364 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
the change is more rapid than in the males, for a female in full summer 
plumage was taken on June 4. 
During the last three days of September 1913, some males taken at 
Humphrey Point were entirely white except for a few brown feathers 
on the crown and sides of the head. Females taken at the same 
time were, with one exception, far less advanced towards full winter 
plumage. 
LAGOPUS LAGOPUS ALEXANDRAE Grinnell. 
ALEXANDER’S PTARMIGAN. 
Quite common but exceedingly wild at Portage Bay, Alaska Penin- 
sula, April 21, 1913. Seven were preserved. 
LAGOPUS RUPESTRIS RUPESTRIS (Gmelin). 
ROCK PTARMIGAN. 
This is an abundant species on the coast from Camden Bay to the 
Mackenzie River delta during the spring and late summer after the 
breeding season which is spent in the foot hills of the Endicott Moun- 
tains. 
At Demarcation Point the first of this species seen in the spring of 
1914 was a pair on May 4. Their late arrival here was a matter of 
chance I believe, for at Humphrey Point, they were seen much earlier. 
They seem to pair earlier than the Willow Ptarmigan, for while the 
latter were about in good-sized flocks the former were mostly paired 
or in groups of three to five. They were very tame in most cases, 
and this I do not understand for the Eskimo has as much oppor- 
tunity to shoot this species as the other. Sometimes both species 
were seen together but very seldom. 
The males are quite pugnacious, when in flocks, often pursuing each 
other and going through antics suggesting the young males of domestic 
fowls. 
Rock Ptarmigan exhibit considerable curiosity at times, a trait I 
have not noticed in the Willow Ptarmigan. When one of its kind is 
dead or wounded the rest frequently show great concern and interest 
in the unfortunate one. 
Many times while walking over the tundra I would be startled by 
the rattling call of a male Rock Ptarmigan, and turning about see him 
alight within a few yards of me with tail spread and eye-wattles erect. 
