590 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
York; crit.).—Exirot, New and Unfig. N. Am. Birds, pt. 12, 1868 (vol. ii), 
. pl. 53, rear fig., and text (wing figured, in text, as that of L. glaucescens),— 
Dat and Bannister, Trans. Chicago Ac. Sci., i, 1869, 304 (Fort Yukon, 
Alaska). 
Larus barrovianus Ripaway, Auk, iii, no. 3, July, 1886, 330 (Point Barrow, 
Alaska; coll. U. 8. Nat. Mus.); Man. N. Am. Birds, 1887, 593.—Turner, 
Contr. N. H. Alaska, 1886, 125 (St. Michaels, etc.; habits)—Nr.son, Rep, 
N. H. Goll, Alaska, 1887, 51 (habits, etc.).—CHarman, Auk, v, 1888, 393.— 
AMERICAN OrNiTHOLOGISTS’ Union Commirres, Suppl. to Check List, 1889, 
5; Check List, 2d ed., 1895, no. 42, 1.—Hnsuaw, Birds Hawaiian Is., 1902, 
126 (Kauai, 2 specs.),—ScHatow, Vég. der Arktis, 1904, 146 (synonymy, 
range, etc.).—Brooxs, Auk, xxi, 1904, 289 (Comox Bay, Brit. Columbia, 
Dec. 15, 1903).—Kurmopz, Provincial Mus. Victoria, 1909, 24 (Comox 
Bay).—Crarx (A. H.), Proc. U. 8. Nat. Mus., xxxviii, 1910, 35 (Patience 
Bay, Sakhalin Island, Sept. 28). 
L{arus] barrovianus Ringway, Man. N. Am. Birds, 1887, 26.—Bryan, Key Birds 
Hawaiian Group, 1901, 6 (Kauai; Maui). 
L{arus] barrowianus Patmn, ‘Vega’-Exped., 1887, 365, footnote. 
Larus glaucescens (not of Naumann, 1840) Taczanowsx1, Mém. Acad. St. Petersb., 
(7), xxxix, 1893, 1019 (e. Siberia). 
LARUS LEUCOPTERUS Faber. 
ICELAND GULL. 
Similar in coloration to L. hyperboreus, but much smaller, with 
relatively smaller bill and feet and longer wing. 
Adults in swmmer (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 gray (between pale and pallid neutral gray, slightly darker than 
in L. hyperboreus), this on remiges fading terminally into white 
(broadly); bill deep yellow or orange-yellow, sometimes greenish 
yellow terminally, the mandible with a lateral and subterminal spot 
of red; iris pale yellow; naked orbital ring orange-red (in life); legs 
and feet pale flesh color (in life). 
Adults vn winter.—Similar to the summer plumage, but head and 
neck streaked with dark grayish, naked orbital ring yellow (in life) 
and legs and feet paler flesh color. 
Young.—Head and neck broadly streaked with brownish gray and 
grayish white, the upper parts coarsely spotted and mottled with 
the same; under parts nearly uniform light brownish gray. 
Adult male-—Wing, 379; tail, 155; exposed culmen, 44.5; tarsus, 
53; middle toe, 48.¢ 
Adult female.—Wing, 393.7; tail, 165; exposed culmen, 40.5; tar- 
sus, 53.3; middle toe with claw, 53.3.% 
@ One specimen, 
Four adults with sex undetermined measure as follows: Wing, 391.2419 (404.1); 
tail (one specimen), 170.2; exposed culmen, 41.9-48.3 (43.8); tarsus (three specimens), 
2.1-55. 9 (54.6); middle toe (three specimens), 44.4-49.5(47). 
