294. 
male of this species, or the next, was observed sitting on eges 
in a marshy plain, at the end of Lake Tsoomourari in Thibet. 
(Five males and seven females, measured and weighed.) 
The fourth primary is the longest. The 1st is from 3°4:to 3°8 shorter, the 
2nd from 0°85 to 1:25, and the 3rd from 0°05 to 0°21, shorter than the 4th. 
Exterior tail feathers from 0°7 to 1°4, shorter than central feathers. 
Description.—Legs and feet, bright, somewhat orange yellow, claws 
black. Lrides yellow. Bill bluish black; cere, yellow, in some a wax yellow, 
in others tinged greenish. 
Prumacre.—Adult male. The upper parts, (except the first six primaries 
and the upper tail coverts,) together with the chin, throat, cheeks, ear-coverts, 
sides of the neck, and a portion of the upper part of the breast, greyish blue, 
varying in tint according to age, (the young birds being darker,) but always 
palest on the wing-coverts and tail, purest on the sides of the neck, and more 
or less tinged with fuscous on the scapulars, crown of the head and nape; 
the feathers of the nape pure white, except just at the tip, the white bases 
showing through more or less; the feathers of the top of the head and nape 
often with narrow, central, somewhat indistinct, brown centres, the traces 
probably of immature plumage ; the forehead, and a line over the eye, whitish ; 
traces of a silvery line under the eye, and over the ear-coverts, and tiny silvery 
streaks, are mingled with the pure blue grey of the ear-coverts and cheeks ; 
the upper tail coverts pure white, the lateral tail feathers growing paler on the 
outer webs, until these in the two exterior feathers are pure white except 
just at the tips; the inner webs of all but the two central feathers white, less 
and less strongly tinged with brownish grey, as they recede from the centre, 
and with from 6 to 8 imperfect, transverse, brownish grey, bars, which in old 
birds become almost obsolete, and traces of some of which are generally to 
be met with, on the outer webs also, of the two or three exterior feathers, on 
each side. The lower breast and the rest of the under parts, are white. 
suffused most strongly on the breast, and faintly elsewhere (except in quite 
old birds which are sometimes pure white below) with very pale bluish grey, 
The first 6 primaries are black or blackish brown, the outer webs, (especially 
towards the tips) and often the tips themselves, more or less suffused with 
silver grey; the inner webs white at the bases; the rest of the primaries and 
secondaries, silver grey on the outer webs and tips, white or greyish white on 
the inner webs above the tips, in some mottled with grey, and mostly shewing 
traces, near the shafts, of imperfect brown, transverse bars. 
Female.—The forehead, a narrow band over the eyes, the lores, cheeks and 
a line over the ear-coverts fulvous white. The crown of the head, occiput 
and nape, reddish fawn, the feathers with long, rich brown, central stripes. 
The ear-coverts and a line from them to the gape, similar, but of a somewhat 
duller colour. The feathers of the nape, white for the basal two-thirds ; 
the white often shewing through. The feathers ofthe ruff a somewhat lighter 
reddish fawn, with narrow, dark brown, central stripes, the hind-neck, and 
upper back, a mixture of reddish and yellowish fawn colour, the feathers 
with broad, umber brown, central streaks; the scapulars, interscapulary 
region, lower back, and rump, umber brown, more or less glossed with 
purple, lighter in the old birds, darker in the young. The feathers of the 
rump, generally narrowly tipped with pale rufous ; the upper tail coverts, as 
a rule, pure white but in some cases exhibiting lanceolate, rufous, or rufous 
brown spots on the shaft. The tail which, quite at the base, is white, has the 
central feathers brown ; deep brown in younger birds, and greyer and paler in 
older ones, narrowly tipped, with white or slightly rufous white, and with four 
