Adult Male. Plate CCCLXXI. Fig. 1.
Bill shortish, strong, somewhat compressed; upper mandible with the dorsal line arcuato-declinate, the ridge flattened at the base and narrowed on account of the great extent of the nasal sinus, which is feathered, the sides convex toward the end, the edges inflected, the tip narrow and rounded; lower mandible with the angle of moderate length and width, the dorsal line ascending and convex, the edges sharp and inflected, the tip obtuse, but like the upper thin-edged. Head rather small, oblong; neck of moderate length; body full. Feet rather short, stout; tarsus roundish, feathered, bare and reticulated behind. Toes of moderate size, covered above with numerous scutella, laterally pectinated with slender projecting flattened scales; first toe small, second a little shorter than fourth, third much longer. Claws stout, slightly arched, moderately compressed, obtuse.
Plumage dense, soft, rather compact, the feathers in general broadly ovate; those on the head very short, on the sides of the neck anteriorly at its lower part and across the fore part of the breast, small, very short, broad, stiff, and imbricated like scales; higher up on the sides of the neck a tuft of feathers having their shafts elongated, bristle-like, and terminated by a few filaments. On each side of the lower part of the neck in front is a large bare space capable of being inflated into a hemispherical sac. On the fore part of the breast the feathers, although long, have the shaft thickened and elongated; the rest of the feathers are of ordinary structure. Wings rather short, concave, much rounded, the primaries stiff and very narrow, so as to leave a large interval when the wing is extended; the third, fourth, and fifth quills longest. Tail long, graduated, of twenty stiffish feathers, each tapering to a very elongated point.
Bill black; iris light hazel; superciliary membrane vermilion; toes brownish-grey; claws brownish-black. The upper parts are light yellowish-brown, variegated with brownish-black and yellowish-white; the feathers of the head and neck transversely barred, of the back barred, undulated and dotted, with a whitish longitudinal line along the shafts of the wing-feathers. The quills chocolate-brown, their outer webs and part of their inner margins mottled with yellowish-white. Tail with about ten bands of yellowish-white on the outer webs, which are otherwise variegated like the back, the inner webs nearly plain brown. The throat and fore part of neck whitish, longitudinally spotted with brownish-black; a narrow white band across the throat; the sides of the neck and fore part of the breast white; the elongated shafts of the tuft-feathers, black; the sides variegated like the back with a broad line of white along the middle of each feather; the axillars and lower wing-coverts pure white; the hind part of the breast and the abdomen, brownish-black; the sides of the rump like the back, the lower tail-coverts brownish-black, largely tipped with white, the feathers of the tibiæ and tarsi pale brownish-grey, faintly barred with brown.
Length to end of tail 30 inches; extent of wings 36; wing from flexure 13; tail 12, shortest feathers 7; bill along the ridge 1 6/12, along the edge of lower mandible 1 4/12; tarsus 2 1/2; hind toe 1/2, its claw 4/12; middle toe 2 1/4, its claw 6/12.
Adult Female. Plate CCCLXXI. Fig. 2.
The female is much smaller than the male, and differs in being destitute of the bare skin on the fore neck, in having the superciliary membranes smaller, the plumage entirely of ordinary texture; the tail less elongated, with the feathers less narrow and ending in a rounded point. All the upper parts, fore neck and sides are variegated with brownish-black, yellowish-grey and whitish disposed nearly as in the male; the throat whitish, the fore part of the breast white, the middle part brownish-black, the legs and tarsi as in the male, as are the quills; the tail-feathers mottled like the back and tipped with white.
Length to end of tail 22 inches; wing from flexure 10 1/2; tail 7 3/4; bill along the ridge 1 4/12; tarsus 1 10 1/2/12; middle toe 1 8 1/2/12, its claw 6/12.
The size of this species has been exaggerated, it having been by some compared to the Turkey, and by others to the Great Wood Grous of Europe, Tetrao Urogallus, whereas, in fact, it seems not much to exceed Tetrao hybridus. In some individuals, as I am informed by Dr Townsend, the hair-like shafts of the feathers on the sides of the neck, are considerably longer than in my figure of the male.