298 BLACK-THROATED DIVER. 



Bill black. Iris deep bright red. Feet greyish-blue, their inner sides 

 tinged with yellow; claws black, that of the inner toe yellowish at the base. 

 The upper part of the head and the hind neck are light grey or hoary, the 

 fore part and sides of the head darker. The upper parts are glossy black, 

 tinged with green anteriorly, and shaded with brown behind. On the fore 

 part of the back are two longitudinal bands of transverse white bars, the 

 feathers, being tipped with that colour; the scapulars, excepting the outer, 

 are marked in the same manner with transverse rows of rather large square 

 spots. Most of the wing-coverts have two roundish spots of white near the 

 end. The quills are blackish-brown, tinged with grey externally, paler on 

 the inner webs; the tail also blackish-brown. The fore neck, to the length 

 of six and a half inches, is purplish-black, ending angularly below, and with 

 a transverse interrupted band of linear white spots near the upper part; 

 beyond which the sides of the neck are blackish-brown, with several 

 longitudinal white streaks, formed by the edges of the feathers; on the lower 

 part of the neck a broad space is occupied by these longitudinal, dusky, and 

 white streaks, the former of which gradually become narrower. The lower 

 parts are pure white, excepting a longitudinal band on the sides under the 

 wing, which is dusky. 



Length to end of tail 29 inches, to end of wings 27^-, to end of claws 33; 

 extent of wings 39^; wing from flexure 12f ; tail 2f; bill along the ridge 

 2y|, along the edge of lower mandible 3y§; tarsus 3^', hind toe T 8 2, its claw 

 T 2 2-; second toe 3 T 2 2, its claw -ff; third toe 3 T 8 2, its claw 5-ff; fourth toe 4i, its 

 claw *!■. 



Adult Female. 



The female is smaller than the male, but is similarly coloured. 



Young in winter. 



The texture of the plumage is less dense, the feathers on the neck being 

 more downy, and those of the back oblong and rounded. The bill is light 

 bluish-grey, dusky along the ridge; the iris brown; the feet more dusky. 

 The upper part of the head and the hind neck are dark greyish-brown; the 

 sides of the head greyish-white, minutely streaked with brown. The upper 

 parts have a reticulated or scaly appearance, the feathers being brownish- 

 black, with broad bluish-grey margins; the rump dull brownish-grey. The 

 primaries and their coverts are brownish-black, the secondaries and tail- 

 feathers dusky, margined with grey. The fore part of the neck is greyish- 

 white, minutely and faintly dotted with brown, its sides below streaked with 

 the same; the lower parts, including the under surface of the wing, pure 

 white; the sides of the body and rump, with part of the lower tail-coverts, 

 dusky, edged with bluish-grey. 



When in their first downy plumage, the young are of a uniform brownish- 

 black colour. 



