In the pigeon-footed families the hind toe, or hallux, is on the same plane as the three others, which are directed forwards ; but the fowl-footed have the hallux usually very small and raised, sometimes barely touching the ground.

The sternum has a double bifurcation on each side, the fissures wide and deep, and provides but little space for the attachment of the pectoral muscles.

These last are, however, well developed, giving the plump appearance characteristic of these birds.

The tail is frequently short, of various shapes, but in the Phasianidaa it is sometimes lengthened to an extra- ordinary degree.

The flight is labored, but rapid, and not often extended to any con- siderable distance.