A single family, in external appearance and habits resembling Partridges. They inhabit either open plains, forests, or rocky mountains, but are always found on the ground, and fly badly. Their eggs are highly polished and uniformly coloured, the colour varying with the particular species. As in the Ratitae, the male bird appears generally to perform the duty of incubation.
Tinamous have a small head and slender neck, clothed with very short feathers. Upper mandible of the bill is covered at base with a cere which also envelops the nasal grooves. The general plumage is inconspicuous, ranging from rufous to slaty, often more or less closely barred. In size they vary from that of a quail to that of a fowl, or from 6" to 21" in length. Wing short and rounded. Fifth secondary present. Ten primaries. Tail short, pendant,, and generally hidden by the upper tail-coverts. Tarsus shielded or reticulated. Powder-down patches present, and these in some have after-shafts. Oil-gland tufted. Young are hatched covered with down, and resemble those of some of the Ratitae.
The existing sixty-five known species are all inhabitants of the Neotropical region, being widely distributed throughout S. America, and as far N. as Central Mexico. The presence or absence of a small and elevated hind toe has given rise to a division into two subfamilies, viz.—
Tinaminae (with hind toe raised), containing the large majority of the group ; and Tinamotidinae (without hind toe), containing only three species.