Some philosophers, from particular system, have judged from a certain disposition of this animal’s scales, that it is what they term, Coluber, while others, from some arrangement of the scales of its tail, will have it to be what they call Boa. I enter not into the dispute, it is here as faithfully represented as the size will permit, only I shall observe that, unless Boa means something more than I know it does, the name is ill chosen when applied to any species of poisonous serpents, because it is already the proper name of the large snake, just mentioned, that is not viviparous, and has no poison. Pliny and Galen say, that the young vipers are so fierce as to become parricides, and destroy their mother upon their birth. But this is surely one of the ill-grounded fancies these authors have adopted. The Cerastes is mentioned by name in Lucan, and without warranting the separate existence of any of the rest, I can see several that are but the Cerastes under another term. The thebanus ophites, the ammodytes, the torrida dipsas, and the prester[91], all of them are but this viper described from the form of its parts, or its colours. Cato must have been marching in the night when he met this army of serpents. The Cerastes hides itself all day in holes in the sand, where it lives in contiguous and similar houses to those of the jerboa, and I have already said, that I never but once found any animal in this viper’s belly, but one jerboa in a gravid female cerastes. I kept two of these last-mentioned creatures in a glass jar, such as is used for keeping sweetmeats, for two years, without having given them any food; they did not sleep, that I observed, in winter, but cast their skins the last days of April. The Cerastes moves with great rapidity, and in all directions, forward, backward, and sideways. When he inclines to surprise any one who is too far from him, he creeps with his side towards the person, and his head averted, till judging his distance, he turns round, springs upon him, and fastens upon the part next to him; for it is not true what is said, that the Cerastes does not leap or spring. I saw one of them at Cairo, in the house of Julian and Rosa, crawl up the side of a box, in which there were many, and there lye still as if hiding himself, till one of the people who brought them to us came near him, and though in a very disadvantageous posture, sticking as it were perpendicular to the side of the box, he leaped near the distance of three feet, and fastened between the man’s forefinger and thumb, so as to bring the blood. The fellow shewed no signs of either pain or fear, and we kept him with us full four hours, without his applying any sort of remedy, or his seeming inclined to do so.