Head, neck, and all the under parts, white; cheeks and occiput greenish black: bill and legs bluish gray: crest (in the adult male) bushy, moderately elongated.
M. albellus, Temm. Man. d'Orn. tom.ii. p. 887. Smew, Mont. Orn. Diet, & Supp. Bew. Brit. Birds, vol. ii. p. 260. Selb. Illust. vol. ii. p. 385. pl. 59. (Trachea,) Linn. Trans, vol. iv. pl. 16. f. 3, & 4.
Entire length seventeen inches: length of the bill (from the forehead) one inch three lines, (from the gape) one inch eight lines; of the tarsus one inch six lines.
(Adult male). A large patch on each side of the base of the bill enclosing the eyes, and another longitudinal one on the occiput, black glossed with green; rest of the head, occipital crest, neck, some of the lesser wing-coverts, and all the under parts, pure white: two crescent-shaped fasciae advancing forwards from the shoulders on each side, and partly encircling, one the lower part of the neck, the other the upper part of the breast, black; back, lesser coverts bordering the wing, and primary quills, black; scapulars white, edged on the outer webs with black; secondary quills and greater coverts black, tipped with white: tail and upper tail-coverts bluish gray: flanks and thighs with transverse undulating lines of black: bill and legs deep bluish gray; the membranes of the toes dusky. (Female). Crown, cheeks, and occiput, reddish brown; crest shorter than in the male; throat, sides and front of the upper part of the neck, belly, and abdomen, white; lower part of the neck, breast, and flanks, clouded with ash-colour: back, tail, and upper tail-coverts, deep ash-gray: wings much as in the male, only the dark parts gray instead of black. The young of the year resemble the adult female. After the second moult, the male begins to shew a few black feathers on the sides of the face, the first indication of the large patch which characterizes that part in the adult; some white appears on the crown and occiput; the back becomes partially black; and the two crescent-shaped fasciae are faintly traced out on the sides of the breast. (Egg). " Whitish." Temm.
A winter visitant, but not of very frequent occurrence. Principally met with in the neighbourhood of fresh waters. Breeds in high latitudes on the borders of lakes and rivers. Eggs, according to Temminck, from eight to twelve in number. Food, fish, and aquatic vegetables. Obs. The Minute Merganser of Montagu and other English authors (M. minutus, Linn). is referable to the female and young of this species.