Male with a longitudinal crest; tail graduated, of sixteen feathers; bill black, feet livid blue; head, neck, lower parts, scapulars, and a patch on the wing, white; a short band on each side of the hind neck bordering the crest, duck-green; a broad patch on the lore and below the eye, a narrow band across the lower part of the hind neck, formed by single bars near the tips of the feathers, the middle of the back in nearly its whole length, a short transverse bar under the fore edge of the wing, the anterior margin to beyond the carpal joint, the outer edge of the scapulars, the primary coverts, secondary coverts, and outer secondary quills, excepting the tip of both, deep black; quills also black, of a less deep tint; hind part of back tinged with grey; rump and tail-feathers dusky grey; sides of body and rump white, finely undulated with blackish-grey. Female much smaller, similarly crested; all the lower parts white, excepting a belt across the lower fore part of the neck, and a narrow portion of the sides, which are pale grey; a patch of brownish-black on the lore and beneath the eye; upper part of head and half of hind neck light reddish-brown; the rest of hind neck and all the upper parts bluish-grey, darker behind, and in the middle of the back approaching to black; tail dusky grey; wings, bill, and feet as in the male. _Male_, 17-1/2, 27. _Female_, 15-1/2, 25. Exceedingly rare in America, one specimen only having been procured at New Orleans. Smew or White Nun, Mergus Albellus, Wils. Amer. Orn. v. viii. p. 126. Mergus Albellus, Bonap. Syn. p. 398. Smew or White Nun, Nutt. Man. v. ii. p. 467. Smew or White Nun, Mergus Albellus, Aud. Orn. Biog. v. iv. p. 350. FAMILY XLI. PELECANINÆ. PELICANS.