COLYMBUS. 
133 
BIRDS. PALMIPIDES. 
ridge of tlie lower mandible sloping upwards, giving the bill a recurved as- 
pect ; the grove at the symphysis continued to within about 3 lines of the tip. 
Feet, on" the outside, dusky; pale within. Irides brown. Tongue entire, 
pointed. Vermiform appendages I inch long, and upwards of | inch broad. 
Head and neck black, the latter with two collars, white, freckled with black. 
Back black, with white spots. Breast and belly white. Tail of 20 feathers. 
Female similar, but less — Nest on the margin of fresh-water lakes. Eggs 2, 
Isabella yellow, Avith purplish-grey spots. Young differ in the plumage above, 
being brownish-black, freckled with grey on the cheeks, and the feathers on 
the back edged with grey ; below, rvhite, with a dusky bar across the vent. 
In this state it is the C. immer of Linne. The black on the neck, the col- 
lars, and the white spots on the back, appear as the bird approaches maturity, 
which it reaches at the age of 3 years. — The young of this species are com- 
mon in Zetland, during ivinter, while old birds seldom occur. In Orkney, 
however, both old and young birds abound at that season. The old birds 
visit the Frith of Forth in winter, following the herrings. The young birds 
are occasionally seen in summer in the Zetland seas, and I observed one off 
the coast of Waterford, 28th July 1816. 
212. C. arctkus. Black-throated Diver. — Bill upwards of 
3 inches in length ; flat above the nostrils ; groove of the sym- 
physis reaching to the end of the lower mandible. 
Will. Orn. 258. Sihb. Scot. 20. Linn. Syst. i. 221. Penn. Brit. Zooi 
ii. 527 . Temm. Orn. ii. 913 — A winter visitant. 
Length 27, breadth 44 inches ; weight 4 pounds. Bill black, nearly 3^ inches 
long, rounded, blunt. Feet brown outwardly, whitish within. Irides brown. 
Front, throat, fore-neck, back, and rump, black. Crown and nape grey. Sides 
of the neck spotted black and white. Sides of the back scapulars and Aving-co- 
vers black, v/ith white spots. Tail feathers 20. Female similar — Nest on 
the margin of lakes. Eggs 2, white, Avith distant black spots. The young 
are dusky above, and Avhite below, at first ; the head then becomes grey, and 
the sides of the neck freckled with black. At two years, the black on the 
fore-neck, and the black and white of the back, make their appearance ; and 
the plumage is complete in 3 years. When approaching maturity, it appears 
to be the Second Speckled Diver of BeAAuck. 
213. C. septentrionalis. Red-throated Diver.— -Bill scarcely 
3 inches long, slender, pointed, subrecurved; groove of the 
symph 3 ^sis of the lower mandible very short. 
Linn. Syst. i. 220. Penn. Brit. Zool. ii. 526, Temm. Orn. ii. 916. — A, 
Bain Goose. — Breeds in Orkney and Zetland. A winter visitant of 
the Thames. 
Length 24, breadth 41 inches ; Aveight upwards of 3 pounds. Bill black, 
much more pointed, slender, and recurved, than the tAvo preceding species ; 
the margins are much incurved. Legs black Avithout, Avhitish on the inside. 
Irides reddish-brown. Crown, nape, and back of the neck, purplish-black, 
the edges of the feathers Avhite and raised. Chin, cheeks, and sides of the 
neck, dark grey. Fore-neck brownish -red ; above, olive-black, with pale edges ; 
wing covers dusky, with white spots. Breast and belly silvery. V ent Avith a 
black bar. Tail of 20 feathers ; the under covers black, with pale edges. Fe- 
male similar — ^Nest on the margin of lakes. Eggs 2, olive broAvn, Avith brown 
spots. Young., at first, dusky above, Avhitish below ; they then assume the 
grey on the head, and become spotted on the back ; and, on approaching ma.c 
turity, the red on the throat appears. In its immature state it is the First 
Speckled Diver” of BeAvick. Linnaeus states, that, in SAveden, the Black 
Throated Diver Avas considered as the male of this species. I have seen the 
Bed and Black Throated Divers in company Avith a young bird, and had evi- 
