I have drawn it here of its natural size, which is 6-1/6 inches. Though its legs are very long, it does not make use of them to stand upright, but creeps with its belly almost close to the ground. It runs, however, with very great velocity. It is very long from its shoulder to its nose, being nearly two inches. Its body is round, having scarce any flatness in its belly. Its tail too is perfectly round, having no flatness in its lower part. It is exceedingly sharp-pointed, and very easily broke, yet I have seen several where the part broke off has been renewed so as scarcely to be discernible. It is the same length, 2-1/6 inches, between the point of the tail and the joint of the hinder leg, as was between the nose and the shoulder of the foreleg. Its forehead from the occiput is flat, its shape conical, not pointed, but rounded at the end in the shape of some shovels or spades. The head is darker than the body, the occiput darker still; its face is covered with fine black lines, which cross one another at right angles like a net. Its eyes are small, defended with a number of strong black hairs for eye-lashes. Its upper jaw is longer, and projects considerably over the under; both its jaws have a number of short, fine, but very feeble teeth, and when holding it in my hand, though it struggled violently to get loose, it never attempted to make use of its teeth; indeed it seems to turn its neck with great difficulty. Its ears are large, open, and nearly round. Its body is a light-yellow, bordering on a straw-colour, crossed with eight bands of black, almost equally distant, except the two next the tail. All these decrease both in breadth and length from the middle towards each extremity of the animal. The scales are largest along the back, they are very close, though the divisions are sufficiently apparent. Their surface is very polished, and seems as if varnished over. Its legs from the shoulder to the middle toe are nearly an inch and three quarters long; its feet are composed of five toes, the extremity of each is armed with a brown claw of no great strength, whose end is tipt with black. I have heard some of the common people call this lizard Dhab: This we are to look upon as an instance of ignorance in the vulgar, rather than the opinion of a naturalist well informed; for the Dhab is a species perfectly well known to be different from this, and is frequently met with in the deserts which surround Cairo. CERASTES, OR HORNED VIPER.