outside eggs in under the body, and by the way it seats itself on the nest. It squats at the edge, and then gradually, in a sliding manner, works itself in, until it covers the eggs, dragging in sand during the process, and thus silting up the nest. The Ostrich, being a large, heavy, long-legged bird, when about to squat, bumps with a hard jerk on to its "knees," and then gently lets its body down to the ground. So, when getting on to a nest, it carefully places its feet among the eggs, bumps down with its "knees" outside the nest, clear of the eggs, and then works itself in till the nest is covered. If this method were not pursued the eggs would be broken by the sudden and violent impact with the "knees" as the bird bumped down.
Now the use of the bank, and the reason for its gradual, continuous formation after sitting begins, are apparent; the nest is thus kept hollow. Without it the nest would be liable to silt up and the eggs roll away. That this is its use seems to be clearly shown by the fact that the nest, though hollow, is at times slightly raised above the original level. The embankment, lying close to the bird's body, also serves to carry off some of the rain that falls on the bird, as well as to partly prevent running water entering the nest.
Guarding the Nest.
The cock is very vicious and pugnacious, and will attack any bird or any person approaching the nest; at times he will chase and kick at bucks, jackals, porcupines, and other animals. If, however, a person gets right up to the nest, especially if he kneels or sits beside it, the cock seldom kicks, but puts his head down to the ground, snaps his beak spasmodically, hissing violently meanwhile, and tremulously flutters his wings (which click loudly at the largest joint) in impotent excitement and distress. But if one is only a few yards off he will kick and fight most determinedly. The reason seems obvious: if he kicks at the nest he will almost certainly break the eggs.
The hen is not vicious, and does not fight, except when she has chicks; then the habits of the cock and hen change to some extent; the cock generally runs away with the chicks (he will fight if necessary), while the hen advances to do battle.
