"Adult.--Above brown, inclining to ashy on head and upper back, and to rufous on lower back, rump, and upper tail-coverts, the latter of which are plainly barred and broadly tipped with pure white; forehead white; sides of face clear ashy gray; sides of neck ashy brown, uniform with the interscapulary region; wing-coverts rufous-brown, mottled with clearer rufous; primary-coverts rufous, externally mottled and broadly tipped with black; quills rufous, narrowly tipped with buffy white, primaries brown externally and toward their tips, also barred with dark brown on their inner webs; the secondaries ashy brown, inclining gradually to whity brown at their tips, washed with rufous and barred with dark brown; the lower surface of the wing creamy white on the inner webs of the quills, somewhat washed with rufous; tail ashy brown, whity brown at tip and crossed with three or four broad bars of blackish brown, the lower surface ashy white, the bars showing more plainly, except on the outermost feather, where they are obsolete; throat white, with a mesial line of ashy brown, as well as two not very distinct moustachial streaks; upper breast ashy brown, washed with rufous, the lower breast and abdomen barred with white and rufous-brown, the latter bars decreasing toward the vent and thighs, and totally absent on the under tail-coverts; under wing-coverts with slight cross-markings of pale rufous. Bill leaden black, yellow at base; cere and feet yellow; iris yellow. Length, 470; culmen, 33; wing, 333; tail, 201; tarsus, 61. "Adult female.--Larger. Length, 470; wing, 345; tail, 213; tarsus, 62. "Young.--Considerably different from the adult. Above dark brown, the wing-coverts washed with rufous and tipped with dull white, the greater ones with rufous or rufous-white spots on both webs, giving a mottled appearance to these parts; forehead and eyebrow creamy white; crown and hind neck brown, the feathers margined with creamy white, giving a striped appearance, the latter also slightly washed with rufous; sides of face ashy brown, streaked with darker brown, the fore part of the cheeks white; under surface of body creamy buff, the throat with a central blackish streak on the lower part; center of chest streaked with dark brown, the breast with pale chestnut, becoming spade-shaped spots on the flanks, but narrowing to small streaks on the thighs, and disappearing altogether on the under tail-coverts, which are creamy buff; under wing-coverts creamy buff, with a few rufous-brown marks on the lower series, and bars of the same on the axillars; upper tail-coverts brown, white at the base and at tip, and having the outer margin also white; tail ashy brown, tipped with pale rufous-brown and crossed with five bars of darker brown, the subterminal one broader; quills dark brown, the secondaries paler, the base of the inner web white, with remains of ashy bars on the inner secondaries. Cere and feet yellow; bill black; iris yellow." (Sharpe.)