BIRDS OF NORTH AND MIDDLE AMERIOA. 597 
Larus] nelsoni Riwaway, Man. N. Am. Birds, 1887, 27. 
[Larus] nelsoni SHarre, Hand-list, i, 1899, 142.—Forpzs and Rosinson, Bull. 
Liverp. Mus., ii, no. 2, 1899, 58. 
[?] Larus kumlient (not of Brewster) Murpocu, Exped. Point Barrow, 1885, 123 
(Point Barrow, Alaska). 
LARUS GLAUCESCENS Naumann. 
GLAUCOUS-WINGED GULL. 
Adulis in summer (sexes alike).—Head, neck, rump, upper tail- 
coverts, tail and entire under parts, including axillars and under 
wing-coverts, immaculate pure white; back, scapulars, and wings 
uniform pale neutral gray (deeper than in JZ, leucopterus), the second- 
aries extensively and rather abruptly white distally, the primaries 
becoming darker (the fourth and fifth, from outside, abruptly so) 
subterminally, and abruptly tipped with white; outermost primary 
with an additional white space immediately anterior to a sub- 
terminal spot 25 mm. or. more long of deep gray, the second (from 
outside) gray to extreme tip or else with a very small white tip, and 
small white spaces at some distance from tip on one or both webs; 
sixth primary (from outside) with a broad subterminal bar or band 
of deep gray, preceded by a white area; bill yellow, whitish at tip,. 
the mandible with a subterminal lateral spot of red; rictus flesh 
color; iris light yellowish gray or dull creamy white; naked orbital 
ring reddish flesh color (in life); legs and feet flesh color. 
Adults in winter.—Similar to the summer plumage, but head and 
neck clouded with brownish gray; bill paler yellow or yellowish 
white, more decidedly yellow on culmen and tomia. 
Young.+General color deep gray, nearly uniform on under parts 
but on upper parts broken by a coarse irregular spotting or mottling 
of grayish white or pale dull buffy, the head and neck indistinctly 
streaked; primaries and rectrices plain pale brownish gray, with a 
slight glaucous cast, the outermost rectrices more or less distinctly 
mottled with paler; bill blackish, paler basally; legs and feet brownish 
(in dried skins). 
Immature.—Back, scapulars, etc., mixed pale gray and brownish 
gray or grayish brown; primaries and tail uniform brownish gray; 
head and neck grayish white clouded with brownish gray; under 
parts nearly uniform brownish gray; bill yellowish for basal half and 
tip, the intermediate portion dull blackish; legs and feet dull brownish 
(in dried skins). 
Downy young.—Head, neck, and under parts dull buffy white, 
deepening into very pale buffy grayish on back, rump, and flanks; 
pileum and sides of head with a greater or less number of well-defined 
irregular spots of black, one on median portion of forehead, at base 
of culmen, the arm-wing with several large blackish or dusky spots, 
