The small lizard here described is a native of Atbara beyond the rains, in that situation where we have said the island and city of Meroë formerly were. It seemed also to be well known by the different black inhabitants that came from the westward by the great caravan which crossed the desert north of the Niger, and is called the Caravan of Sudan, of which I have often spoken, as being the only barbarians who seem to pay the least attention to any articles of natural history. These bring to Cairo, and to Mecca, multitudes of green paroquets, monkeys, weasels, mice, lizards, and serpents, for the diversion and curiosity of the men of note in Arabia, or of the Beys and the women of the great at Cairo. This lizard is called El Adda, it burrows in the sand, and performs this operation so quickly, that it is out of sight in an instant, and appears rather to have found a hole, than to have made one, yet it comes out often in the heat of the day, and basks itself in the sun; and if not very much frightened, will take refuge behind stones, or in the withered, ragged roots of the absinthium, dried in the sun to nearly its own colour. Almost the whole of this large tribe of lizards is, by the Arabians, described as poisonous. Experiment has detected the falsehood of this, in very many species; the same idea has led them to attribute to them medicinal virtues in the same proportion, and, I am apt to believe, with nearly as little reason; at least, though the books prescribing them are in everybody’s hands, the remedy is not now made use of in the places where those books were wrote; and this affords a strong proof that the medicine was never very efficacious. The El Adda is one of the few which the Arabs in all times have believed to be free of poisonous qualities, and yet to have all the medicinal virtues that they have so abundantly lavished upon the more noxious species. It has been reputed to be a cure for that most terrible of all diseases, the Elephantiasis; yet this distemper is not, that I know, in the hotter parts of Africa, and certainly this lizard is not an inhabitant of the higher or colder parts of Abyssinia, which we may call exclusively the domicil of the elephantiasis. It is likewise thought to be efficacious in cleansing the skin of the body, or face, from cutaneous eruptions, of which the inhabitants of this part of Africa are much more afraid than they are of the plague; it is also used against films, and suffusions on the eyes. I never did try the effect of any of these, but give their history solely upon the authority of the Arabian authors.