BIRDS OF NORTH AND MIDDLE AMERICA. AT 
mostly white, but broadly margined terminally with fuscous, some- 
times so broadly as to reduce the white to an irregular spotting, the 
chest, sides, and flanks sometimes nearly uniform fuscous; axillars and 
under wing-coverts uniform fuscous; bill black; iris dark brown; 
legs and feet pale brownish (flesh color in life). _ 
Winter plumage.—Upper parts dusky (dark fuscous), interrupted 
by a nuchal band of white, the interscapulars, rump feathers, and 
upper tail-coverts tipped with gray; scapulars mostly white, espec- 
ially the inner ones; entire under parts, including malar, auricular, 
and suborbital regions and lower half of loral region, immaculate 
white, the sides and flanks more or less striped with dusky grayish; 
axillars and under wing-coverts uniform fuscous, as in summer. 
Young.—Above uniform dusky (fuscous-blackish), the nape 
somewhat intermixed with white; white scapular patch less distinct 
than in winter adults; lores almost wholly dusky; under parts white, 
nearly everywhere, but more especially on chest, breast, and sides, 
transversely mottled with dusky or fuscous; bill smaller and weaker 
than in adults. 
Adult male.—Wing, 121.5-129 (126.1); tail, 29-35 (31.3); exposed 
culmen, °-13.5-16.5 (15.1); tarsus, 15.5-16.5 (15.9); middle toe, 23- 
25.5 (24.3). 
Adult female. —Wing, 112-127 (121.7); tail, 28-33 (30.5); exposed 
culmen, 15-16 (15.4); tarsus, 15-16 (15.5); middle toe, 22-24 (23).° 
Pacific coast of North America; breeding from Vancouver Island, 
Queen Charlotte Islands, etc., British Columbia to Kodiak and Una- 
laska islands, Alaska; trifle in winter as far as San Diego Bay, 
southern California. 
[Colymbus] marmoratus GuE.in, Syst. Nat., i, pt. ii, 1789, 583 (Prince William 
Sound, Alaska). 
[ Uria] mermorata Latoam, Index Orn., ii, 1790, 799. 
a Ten specimens. > Six specimens. 
Ex- 
. - + posed | m,.... | Middle 
Locality. Wing.) Tail. | © oui | Tarsus.) "oe, 
men. 
MALES. 
Seven adult males from Alaska............-..2.020--ecee cece 125.8 30.8 14.6 15.8 24.1 
One adult male froma Vancouver Island ...............----+--- 129 35 16 16.5 25 
Two adult males from Washington.................--------+-- 126 31.5 16.2 16.2 24.5 
FEMALES. 
For adtilt females from, Alask0.. 6.0002 20u2Kaesonexecessieece 120.6 30.5 15.4 15.5 23.5 
Two adult females from Washington.........-----------+--+-- 123.7 30.5 15.5 15.7 23.7 
