COLYMBIN^. PODICEPS. 
355 
head and hind neck longitudinally streaked with greenish-black and 
pure white, each feather black in the middle, with the sides white, the 
colours disposed in lines ; upper parts in general brownish-black, 
tinged with green, more or less mottled with white, according to age, 
excepting the primary quills and the tail-feathers, of which there are 
twenty ; lower parts pure white, excepting the feathers on the sides 
under the wings, some of those about the vent, and the lower tail-co- 
verts, which are greyish-brown, with white margins and tips. Young, 
in winter, with the fore part of the neck white, or slightly mottled 
with red ; all the feathers of the upper parts with two white spots near 
the end ; tail-feathers edged and tipped with white. Young at first 
covered with dense elastic down, of a greyish-black colour, tinged 
with brown. 
Male, 19, 25. Female, 18, 24. 
Not uncommon during winter, autumn, and early spring, from Mary- 
land eastward. Breeds in Newfoundland, Labrador, and as far north 
as the Arctic Seas. 
Colymbus septentrionalis, Bonap. Syn. p. 421. 
Red-throated Diver, Colymbus septentrionalis, Swains. & Rich. F. Bor. Amer. 
V. ii. p. 476. 
Red-throated Diver, Nutt. Man. v. ii. p. 519. 
Red-throated Diver, Colymbus septentrionalis, Aun. Orn. Biog. v. iii. p. 20 ; v. v. 
p. 625. 
GENUS II. PODICEPS, Lath. GREBE. 
Bill about the length of the head, or shorter, straight, ra- 
ther stout, much compressed, tapering, pointed ; upper man- 
dible with the dorsal line declinate and more or less convex 
toward the end, the ridge convex, the sides erect and some" 
what convex, the edges sharp and inflected, the tip narrow ; 
nasal groove rather long, extending to nearly half the length 
of the mandible, feathered at the base ; nostrils linear-ellip- 
tical, basal, rather small, pervious ; lower mandible with 
the angle long and extremely narrow, the dorsal line ascend- 
ing and straight, the sides erect and slightly convex, the 
edges sharp and involute, the tip acute. Head of moderate 
size, oblong, narrowed before ; neck rather long and slen- 
der ; body long, depressed. Feet short, large, placed close 
to the extremity of the body ; tibia feathered to the joint ; 
tarsus extremely compressed, its anterior edge with a row of 
small scutella, the sides broadly scutellate, the posterior ridge 
