Ostriches live in small flocks of only five or six birds. They feed in the morning, chiefly on plants, but they also devour small animals and reptiles. By midday their stomachs are full, and they rest or play, leaping in circles over the sand, regardless of the blazing sun or the heated ground. Then they drink and wander about eating in the afternoon. In the evening they seek their roosting-places. Sight is the ostrich's acutest sense, but its scent and hearing are also sharp. When it is pursued, it darts off with fluttering wings, taking steps ten or twelve feet long. It is always on the look-out for danger, and the zebra likes to keep near it to avail itself of the bird's watchfulness. In North Africa the Arabs hunt the ostrich on swift horses or running dromedaries. Two or three horsemen follow a male, which after an hour's course is tired out, and gradually relaxes its pace. The horses also are tired after such a chase, but one of the riders urges on his steed to a last spurt, rushes past the ostrich, and hits it on the head so that it falls to the ground. The bird is then skinned, the skin being turned inside out so as to form a bag for the feathers. The feathers of the wild ostrich are much finer and more valuable than those of the tame. A full-grown ostrich has only fourteen of the largest white feathers. The hens lay their eggs in a shallow hollow in loamy or sandy soil, and it is the male bird which sits on the eggs. In the daytime the nest may be left for hours, but then the ostriches cover the eggs with sand. The young ones leave their shells after six weeks and go out into the desert. They are already as large as fowls, but then an ostrich egg weighs as much as twenty-four hen's eggs, and measures six inches along its greatest diameter. The ostrich is remarkably greedy, and turns away from nothing. The great zoologist, Brehm, who had tame ostriches under his care, reports that they ate rats and chickens and swallowed small stones and potsherds, and once or twice his bunch of keys disappeared down the stomach of an ostrich. In one ostrich's stomach was found nine pounds of "ballast"--stones, rags, buttons, bits of metal, coins, keys, etc.