BIRDS OF NORTH AND MIDDLE AMERICA. 633 
Immature.—Similar to adults, but subterminal areas of longer 
primaries deep brownish gray or dusky instead of black, and more 
extended, the white tip of some of the primaries wanting; tail some- 
times (in younger individuals) more or less blotched with dusky on 
terminal portion, and upper tail-coverts sometimes (in still younger 
birds) faintly barred with grayish brown. 
Young.—Head, neck, and under parts nearly uniform light brown- 
ish gray or grayish brown; upper parts grayish brown, the feathers 
margined with pale grayish buff, the rump and upper tail-coverts 
pale grayish buff or dull buffy whitish, irregularly, and more or less 
distinctly, spotted with grayish brown; basal half (approximately) 
of tail dull grayish white or very pale grayish, transversely mottled 
with darker, the distal portion deep grayish brown, forming a well- 
defined broad band, the extreme tip whitish. 
Young in first winter—Similar to the first plumage, but light 
colored margins to feathers of upper parts decidedly white; basal half 
of tail uniform grayish white; under parts mostly white, the chest 
and sides spotted or clouded with light grayish brown; upper parts 
more or less tinged with pure light gray. 
Downy young.—General color pale brownish gray or buffy grayish, 
paler and usually more buffy on head, neck, and under parts; head 
with numerous irregular rather large spots of black, of which the 
most conspicuous occupy the anterior portion of forehead (as in L. 
canus) and posterior portion of malar region, respectively; back, 
etc., with large, irregular spots or cloudings of sooty grayish or 
dusky; bill dusky brownish, broadly tipped with lighter and more 
yellowish brown. ; 
Adult male.—Wing, 352-366 (358.9); tail, 187-148 (142.8); ex-* 
posed culmen, 33-38 (36.4); tarsus, 46.5~51 (49.4); middle toe, 37.5— 
41 (39.5).¢ 
Adult female—Wing, 328-354 (344.6); tail, 131.5-139 (134.9); ex- 
posed culmen, 32-37 (34.1); tarsus, 45-48 (46.7); middle toe, 36-38.5 
(87.5).° 
aSeven specimens. b Eleven specimens. 
A . Exposed Middle 
Locality. Wing. Tail. culmen. Tarsus. toe 
MALES, ; 
One adult male from Mackenzie................-... 366 143 38 50 40 
Six adult males from Alaska................--22---- 357.7 142.7 36.2 49, 2 39. 4 
FEMALES. 
Five adult females from Mackenzie................. 347.2 134.3 34.3 46.4 37.2 
Six adult females from Alaska...........-..-.------ 342.5 135.3 33.9 46.9 37.7 
