"Female.--General color of the upper parts dark brown, each feather with reddish brown edges; upper part of the head darker than the sides, which are whitish, thickly speckled with black; a black line behind the eyes; chin and throat whitish; the feathers of the back and scapulars with two, narrow, transverse, bars of buffy brown; under parts whitish, with a reddish tinge on the breast, each feather, except those of the belly, with obscure dark centers; wing as in the male but somewhat duller.
"Young in first plumage closely resembles the female, but the wing-coverts have pale edgings, and the dark centers of the feathers appear also on the belly.
"Males in molting plumage resemble the adult females.
"'Nestling yellowish white on under parts, buff on forehead and throat; a dark brown streak from the forehead to crown, which with the upper parts is brown; a dark loral streak, and two other streaks from behind eye to nape on each side.' (Yarrell.)" (Salvadori.)
This well-marked genus may be recognized by its elongate form, long neck, and long pointed middle tail-feathers.
Anas acuta Linnæus, Syst. Nat. ed. 10 (1758), 1, 126. Dafila acuta Salvadori, Cat. Birds Brit. Mus. (1895), 27, 270; Blanford, Fauna Brit. Ind. Bds. (1898), 4, 447, fig. 116 (head); Sharpe, Hand-List (1899), 1, 219; Oates, Cat. Birds' Eggs (1902), 2, 172; McGregor and Worcester, Hand-List (1906), 38.
Luzon (Steere Exp., Bourns & Worcester, McGregor). Northern Hemisphere, breeding in the northern parts; south in winter to northern Africa, India, Ceylon, China, and Japan and in America to Panama and Cuba.
"Adult male.--Head and upper neck plain hair-brown, darker on crown, and faintly glossed on sides of occiput with purple; upper half of hind neck black, with a white stripe on each side, confluent with the white of lower neck and breast; lower hind neck grayish brown; back, sides, and flanks waved with gray and dusky; upper tail-coverts black, the median broadly edged with gray; longer scapulars velvety black, edged with whitish; wing-coverts uniform brownish gray, the last row broadly tipped with cinnamon, producing a distinct bar; primaries brownish gray, darker toward the tip; speculum varying from dull metallic green to bronzy purple, tipped with white, and crossed by a subterminal bar of velvety black; inner quill of the speculum velvety black with a white band along the inner part of outer web; tertials gray, marked with a velvety black median stripe; abdomen whitish, dusted with gray, lower flanks with a buff tinge; under tail-coverts black, the outer ones white on the outer web; central tail-feathers long, acuminate, and black, remainder of tail-feathers dusky gray, edged with whitish. Bill blackish, with the sides dull lead-blue; feet grayish black; iris dark brown. Length, from 610 to 760; wing, 280; middle tail-feathers, 184 to 240; culmen, 47 to 55; tarsus, 39 to 47.