Worcester's quail is known from four specimens which were purchased in Quinta Market, Manila. It resembles T. whiteheadi but differs from that species in having the bill much deeper. Major E. A. Mearns informs me that he is quite sure that he saw a live bird of this species in Manila, in August, 1907.
Tip of bill horny and strongly convex forming a "nail" which is often of a shade or color different from that of the soft, contracted, basal portion; covering of nostril generally tumid; toes four, three in front, cleft to the base or with a slight web; hind toe not elevated; legs and toes never much lengthened; tarsus either slightly longer or slightly shorter than middle toe without claw; wing flat and rather long; in several genera the primaries variously cut or attenuated; tail usually square or slightly rounded; never forked; in Macropygia and Geopelia the rectrices are greatly graduated. A few genera are terrestrial, but most of them are more or less arboreal and generally capable of strong, swift, and sustained flight. Their food is largely grain and small seeds; the larger species feed on the fruits of trees, rarely on the leaves. The nest is a slight structure of twigs placed on the ground, in a shrub, or in a tall tree. Eggs one or two, pure white or slightly cream-colored; in shape rather long, equal ended, ovals.
Characters same as those given for the Order.
a1. Soles very broad; tarsus stout, more or less feathered, and generally shorter than middle toe without claw.
b1. Nostril coverings flat or but slightly swollen ... Treronidæ (p. 24) b2. Nostril coverings swollen forming a grape-seed shaped prominence on each side of culmen ... Columbidæ (p. 51)
a2. Soles not greatly expanded on sides of toes; tarsus more slender, unfeathered, and longer than middle toe without claw ... Peristeridæ (p. 54)
Soles very broad; tarsus stout, more or less feathered; bill stout or large; gape very wide in some; nostril covering flat or somewhat swollen; tail moderate in length, nearly square; medium to large sized species.
a1. Under tail-coverts long, their tips reaching well beyond toes; size generally smaller; length, 340 mm. or less.
b1. First primary not attenuated; third primary scooped on middle of inner web, except in Phapitreron which has mostly brown plumage. ... Treroninæ (p. 24) b2. First primary abruptly attenuated, except in Spilotreron which has mostly green plumage; third primary normal ... Ptilopodinæ (p. 36)