Head rather small, oblong, compressed. Eyes of moderate size. Neck of ordinary length. Body rather full. Feet rather long, slender; tibia bare, a third part of its length; tarsus somewhat compressed, anteriorly and posteriorly with numerous small scutella; hind toe very small, the rest of moderate length, slender, the fourth slightly longer than the second, the third longest; all free, broadly marginate, flattened beneath, and with numerous scutella above. Claws small, slightly arched, compressed, rather obtuse, that of the third toe much larger, with the inner edge dilated.
Plumage very soft, blended on the head, neck, and lower parts, the feathers rather distinct above. Wings very long and pointed; primaries tapering, obtuse, the first longest, the second two-twelfths of an inch shorter, the rest rapidly decreasing; outer secondaries slightly incurved, inner elongated, straight and tapering, one of them extending when the wing is closed, to an inch and a quarter from its tip. Tail rather short, nearly even, of twelve rather broad feathers which taper to a broad point.
Bill and feet black. Iris dark hazel. Upper part of the head and hind neck light grey, tinged with buff, and longitudinally streaked with dusky; fore part of back and scapulars, variegated with brownish-black and yellowish, and each feather with several spots of the latter and tipped with whitish; the hind part of the back, rump, and upper tail-coverts, white, barred with black; wing-coverts ash-grey, edged with paler. Alula and primary-coverts brownish-black, tipped with white; primaries similar, their shafts and the outer margins of all excepting the first three, white, the inner webs towards the base light grey; secondaries and their coverts grey, margined with white. Tail-feathers ash-grey tinged with brown, and narrowly edged with white. The sides of the head, fore part of neck, breast, and abdomen, rich brownish-orange; lower tail-coverts and feathers of the legs, white, each of the former with a central dusky narrow-shaped or elongated spot, axillaries white barred with dusky; lower wing-coverts dusky with white margins.
Length to end of tail 10 1/4 inches, to end of wings 10 3/4, to end of claws 11 1/2; extent of wings 21; wing from flexure 7; tail 2 9/12; bill along the ridge 1 4 1/2/12, along the edge of lower mandible 1 4 1/2/12; tarsus 1 1/4; hind toe and claw 4/12; middle toe and claw 1 1 1/2/12. Weight 5 1/2 oz.
The female is similar to the male, but considerably larger.
Length to end of tail 10 3/4 inches. Weight 6 ounces.
In Winter. Plate CCCXV. Fig. 2.
Bill greenish-black, eye of a darker brown. Feet dull yellowish-green; claws dusky. The upper parts are deep ash-grey, each feather margined with whitish; feathers of the rump greyish-white, upper tail-coverts white, barred with dusky. The quills and tail feathers as in summer. A band from the bill over the eye to the hind part of head, white; loral space, cheeks, and sides of neck pale grey, streaked with darker; throat and lower parts in general, white; the sides, axillar feathers, and under wing-coverts, barred or spotted with dusky; lower tail-coverts as in summer.
The young in autumn are of a dull light brownish-grey colour above, each feather having a narrow whitish margin, within which is a dusky line. The fore part and sides of the neck, and the fore part of the breast dull greyish-white, with small dusky-grey longitudinal streaks; the band over the eye indistinct, the loral space darker. The bill and feet are of a duller tint, and the eye darker, than in the adult in winter. Weight 4 1/4 oz.
On the roof of the mouth is a double series of small blunt papillæ. The tongue is very slender, 1 1/12 inch long, emarginate and papillate at the base, channelled above, horny beneath, the point rather acute. The œsophagus is 4 3/4 inches long, narrow, its diameter 3 1/2 twelfths. The proventriculus is oblong, 5 1/2 twelfths in diameter, 9 twelfths long. The stomach is an extremely powerful gizzard, of a roundish form, 1 inch and 5 twelfths long, its greatest breadth 1 1/4 inch; the cuticular lining thin, horny, with large longitudinal rugæ. The intestine 25 inches long, its average diameter 3 1/2 twelfths; cœca cylindrical, 3 twelfths long. The contents of the stomach are fragments of mussels and gravel, with which part of the intestine is also filled.