Rheas always lay their eggs in hollows in the ground, and the number of eggs in a nest seems to vary from twenty to twenty-four. The male bird, apparently, sits upon them, the hen taking no part in the task of hatching them out. Neither does she seem to take any care of the little birds when at last they make their appearance, for they always travel about with the cock. CASSOWARIES Of these there are a good many kinds. They are formed like the ostrich and the emu, but have shorter necks, which are sometimes wattled and are marked with patches of brilliant red and blue and green. The legs are stout and the feet are perfectly enormous. But their most striking feature is an odd bony crest upon the top of the head, which is covered with naked skin. Cassowaries are found only in Australia, New Guinea, Ceram, and some of the neighboring islands, and, unlike all the preceding birds, are dwellers in the forest. They are so shy that they are very seldom seen, so that we do not know very much about their habits. The Australian natives, however, often keep them in captivity, and treat them almost as we treat poultry. But they are rather dangerous creatures, for they can kick very hard with their great, strong feet, and are very ready to attack any one who is a stranger to them. Cassowaries only lay from three to five eggs, and it seems that the cock bird alone sits on them, and that he also takes care of the little ones after they are hatched. KIWIS More curious still are the kiwis of New Zealand, whose wings are so very small, and so completely concealed under the feathers of the body, that practically they may be said to have none at all. Besides this, the beak is so long and slender that it reminds one of that of a woodcock or a snipe. The nostrils are placed at the very tip of this beak, which the bird appears to use by plunging it deeply into soft ground, and then smelling for worms. When it finds a worm it seems to coax rather than to pull it out of the ground, and then throws up its head and swallows it whole. Kiwis have several times been brought to the London Zoo, but hardly any one ever saw them, for all day long they were fast asleep among their straw. If the keeper took them out and woke them they would just yawn once or twice, opening their beaks to the widest possible extent, and then fall fast asleep again. After dark, however, these birds become very lively, and will run with such speed that even a dog can scarcely overtake them. This shows that their natural habit is to go abroad and seek their food during the night. The egg of the kiwi is enormously large. Indeed, it is almost a quarter of the size of the bird itself, and when two eggs have been laid and the bird is sitting on them, the ends project beyond the feathers on either side of its body. BUSTARDS The bustards also are able to run very well, and unlike the birds belonging to the ostrich family, they are also able to fly.