BIRDS OF NORTH AND MIDDLE AMERICA. 649 



[Chroicocephahis] subulirostris Buuch, Jouru. fiir Orn., 1853, 105 (North America, 



type in coll. Mainz Mus.). 

 [Gavia] subulirostris Bonaparte, Naumannia, 1854, 213; Compt. Rend., xlii, 



1856, 771. 



Genus HYDROCOLCEUS Kaup. 



Hydrocoloeus Kaup, Natiirl. Syst., 1829, 113. (Type, Larus mimitus Linnseiis.) 



Very small LaricLne (wing less than 225 mm.) with tarsus not longer 

 than middle toe without claw, very slightl}^ 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.) 



HYDROCOLCEUS 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-gra}^, the posterior portion of crown streaked or clouded with 

 the same; a post-auricular spot of blackisli, 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 T). — "The gra}^ of the crown and 

 nape tinged with brownish; wing-coverts and long inner secondaries 



