84 



BULLETIlSr 50, UNITED STATES NATIONAL MUSEUM. 



Winter plumage. — Witliout black on sides of head or under parts, 

 wMch are pale brownish gray, passing into white on under tail- 

 coverts, the foreneck and chest more or less spotted or mottled with 

 darker; speckling on upper parts mostly grayish white, the yellow 

 chiefly confined to rump and upper tail-coverts; no pure white on 

 forehead, superciUary region, or sides of neck; otherwise like summer 

 plumage. 



Young. — Similar to winter adults, but upper parts more generally 

 and conspicuously spotted with yellow. 



Downy young. — Upper parts bufly yellow (colonial bufT, more or 

 less deep), irregularly mottled with black; a band across nape, sides 

 of head, and under parts dull wliite, the breast tinged with pale 

 brownish gray; forehead bufiy white with a median streak of black; 

 a black loral streak and above this a spot of black; a narrow streak 

 from rictus to beneath auricular region, becoming broader posteriorly. 



Adult male.— Wing, 159-183.5 (176.4); tail, 60-75 (67.9); cuhnen, 

 20.5-24 (22.2); tarsus, 38.5-45 (41.9); middle toe, 21-24.5 (22.9).« 



Adult female.— Wing, 176-183 (180.8); tail, 64-70 (66); culmen, 

 22-23.5 (22.5); tarsus, 41-44.5 (43); middle toe, 23-25 (23.9).^ 



Breeding along or near Arctic coast of North America, from Point 

 Barrow, northern Alaska, "to mouth of Mackenzie River, and from 

 Melville Island, Wellington Channel, and Melville Peninsula south 

 to northwestern [shores of] Hudson Bay;"'' winters in southern 

 South America, on open plains of Brazil, Argentina, Paraguay (Gran 

 Chaco; upper Rio Parana), Uruguay (Montevideo; Baliia Blanca: 

 Sierra de la Ventura), and Bohvia (Aguairenda; San Francisco); 

 m.igrates southward from Nova Scotia, New Brunswick, etc., over 

 Atlantic Ocean via West Indies and Bermuda (a few only going 

 south by way of the interior), returning northward through the 

 Mississippi Valley via the continental land area. 



c American Ornithologists' Union Check List, 3d ed., 1910, 127. 



