Page:Lake Ngami.djvu/478

470 only fatal to domestic animals, as wild animals feed undisturbed in parts infested by the insect. Yet many of them, such as oxen and buffaloes, horses and zebras, dogs and jackals, &c., possess somewhat the same nature. Moreover, it bites man, and no danger follows. The sensation experienced has not inaptly been likened to the sting of a flea. The problem to be solved is, what quality exists in domestication which renders domestic animals obnoxious to this poison? "Is man not as much a domestic animal as a dog? Is it the tsetse at all which kills the animal?"

Captain Vardon, of the Indian army, one of the earlier pioneers of the more interior parts of Southern Africa, was among the first to decide the point; for he rode his horse up a hill infested by tsetse, and in twenty days his doubts were removed by the death of his horse.

According to the statement of the celebrated explorers, Messrs. Oswell and Livingstone, who were severe sufferers by the tsetse, the following symptoms are observed in the ox when bitten: the eye runs, the glands under the throat swell, the coat loses its gloss, there is a peculiar flaccidity of the muscles generally, and emaciation commences, which proceeds unchecked until—perhaps months after the bite—purging supervenes, and the animal perishes of exhaustion. Some die soon after the bite is inflicted, especially if they are in good condition, or should rain fall; but, in general, the process of emaciation goes on for many weeks. In some cases the animals become blind before they die.