All the members of the Crocodile Family propagate by egg-production. The eggs are relatively small in size, those of the largest species not exceeding that of a goose in dimensions. In shape they are more or less symmetrically ovate, and encased with a hard, white shell. In the case of the crocodile, the female selects a suitable dry sand-bank near the river's edge, in which it excavates a hole of about 2 feet deep, and, having deposited from twenty to sixty eggs therein, mounts guard over them, sleeping on top of the nest by day, until the young are hatched. With the alligator, the site chosen for the nest is more usually among bushes or reeds at some distance from the water, and the eggs, which may be laid to the number of over 100, are covered over with leaves and vegetable débris, whose decomposition engenders the heat required for their successful incubation. In both instances the parent jealously guards the nest and repels all intruders until the eggs are hatched, and ultimately conducts the young ones to the water, where they soon learn to shift for themselves. Numbers of them, nevertheless, in their young and weak state, fall victims to vultures, hawks, ichneumons, and all manner of birds and beasts of prey. From their birth the little saurians are most vicious and irascible in disposition, hissing and snapping at or laying hold with bull-dog tenacity of a finger or other seizable object that may be held towards them. From their earliest days also they are eminently aggressive and carnivorous. Contenting themselves at first with flies and other insects, they speedily extend their attentions to frogs, lizards, fish, or any small animals which frequent the marshes and river-banks; and finally, with their concurrently increased appetites and dimensions, requisition such larger prey as sheep, goats, deer, horses, and, as before mentioned, even the human species, if they can steal a march on them unawares. Crocodiles are provided with relatively small gullets, and are necessarily incapable of swallowing any prey whole which is of large dimensions. Accordingly any big quarry which is seized and dragged into the river is disposed of piecemeal, the reptile rending the carcase in fragments with the aid of its terrible teeth and side-wrenches of its ponderous body.