GLAUCOUS GULL 441 
DESCRIPTIVE CHARACTERS. 
PLUMAGE. Adult male nuptial.— Head, neck, breast, 
abdomen, and tail, white; back and wings, pale ‘ pearl’ 
grey; scapulars, secondaries, and outermost webs of the 
primaries, tipped with white. 
Adult female nuptial.—Similar in plumage to the male. 
Adult winter, male and female.—Ditfers from the nuptial 
plumage in that the head and neck are streaked with pale 
sreyish-brown. 
Immature, male and female.—The plumage is light buff- 
colour, profusely streaked and mottled with light ashy- 
brown ; outer primaries, light nut-brown on the outer webs, 
paler on the inner webs. With each moult the bird 
becomes lighter, until, for a short time before maturity it 
is entirely pure white. At this phase of plumage, in which 
the ‘pearl’ coloured feathers of the fully adult bird have 
not yet appeared, the Glaucous Gull was described as 
L. hutchinsi of Richardson; Mr. Saunders disposes of the 
idea of a separate species, having watched the successive 
plumage changes in captivity. ; 
Beak. Yellow, orange at the angle. 
FEET. Bright pink. 
IrtpEs. Yellow; margin of eyelids, vermilion-red. 
AVERAGE MEASUREMENTS. 
TOTAL LENGTH ... 29 in. Female smaller. 
WING ©... sa pean bs * 
BBAK 922 uy SL toe vs 
TARSO-METATARSUS ... DAM sven 
HiGG Fae ae Ze! 2°9 2 in. 
Allied Species and Representative Forms.—L. barro- 
vianus of Ridgeway, is a Glaucous Gull of Alaska, but 
Mr. Saunders can find nothing exceptional in specimens 
from the North Pacific, and the Arctic regions ef America, 
including Greenland. But LZ. glaucescens, which inhabits 
the Pacific north of lat. 40° N.1is smaller, and its primaries 
are chequered with pale grey. A large and rare represen- 
tative found in Alaska and Vancouver Island, has been 
named L. nelsoni (Henshaw), while L. kumlient, a smaller 
bird, “with rather more definition in its wing-pattern,” 
