BIRDS OF NORTH AND MIDDLE AMERICA. 649 
[Chroicocephalus],subulirostris Brucu, Journ. fiir Orn., 1853, 105 (North America, 
type in coll. Mainz Mus.). 
[Gavia] subulirostris Bonaparte, Naumannia, 1854, 218; Compt. Rend., xlii, 
1856, 771. 
Genus HYDROCOL@JUS Kaup. 
Hydrocoloeus Kaup, Natiirl. Syst., 1829, 113. (Type, Larus minutus Linneeus.) 
Very small Laride (wing less than 225 mm.) with tarsus not longer 
than middle toe without claw, very slightly longer than exposed cul- 
men, the latter about one-ninth as long as wing; primaries without 
black ‘‘pattern,”’ under wing-coverts gray, and summer adults with- 
out white about eyes. , 
Range.—Subarctic and temperate Europe and eastward to mouth 
of Amur River and Sea of Okotsk. (Monotypic.) 
HYDROCOLEUS MINUTUS (Pallas). 
LITTLE GULL. 
Adults in summer (sexes alike).—Head and upper neck, all round, 
uniform black, without any white about eyes; lower neck (all round), 
entire under parts, lower rump, upper tail-coverts, and tail immacu- 
late pure white; back, scapulars, wings, and upper part of rump uni- 
form pale bluish gray (nearly gull gray, no. 8), the secondaries and 
primaries broadly tipped with white; outermost primary with mid- 
dle portion of outer web edged with blackish; axillars grayish white; 
under wing-coverts gull gray, slightly darker proximally and paler 
toward edge of wing; under primary coverts and under surface of 
primaries plain deep neutral gray; bill lake red (brownish in dried 
skins); iris dark brown; legs and feet vermilion red (in life). 
Adults in winter.—Similar to summer adults, but head and neck 
white, the occiput and nape nearly uniform deep neutral gray or dull 
slate-gray, the posterior portion of crown streaked or clouded with 
the same; a post-auricular spot of blackish, and eyes margined 
anteriorly with black; bill dusky red or dusky brown. 
Young.—Forehead, lores, cheeks, under parts, upper tail-coverts 
and greater part of tail white; occiput, auricular region, lower part 
of nape, lesser and middle wing-coverts, scapulars, tertials, and ter- 
minal third (approximately) of tail, except on lateral rectrices, sooty 
blackish, the feathers, except on head and neck, margined terminally 
with pale buff or whitish; greater wing-coverts and secondaries deli- 
cate pale bluish gray; primaries with outer webs mostly blackish 
(more slaty basally), their inner webs mostly white, except terminally 
and along shafts; primary coverts black; bill blackish; legs and feet 
flesh color (in life). 
Immature (young in first winter ?).—“The gray of the crown and 
nape tinged with brownish; wing-coverts and long inner secondaries 
