Of the asp. The asp, aspis, is so called because it injects poisons with its bite, spreading them throughout the body. For the Greek word for poison is ios, and from this comes the word aspis, because it kills with a poisonous bite. It moves quickly with its mouth always open and emitting vapour. There are various kinds and species of asps which inflict harm with different effects. It is said that when the asp begins to endure a snake-charmer summoning it with music designed for that purpose, to bring it out of its cave, and it does not want to come out, it presses one ear to the ground, and blocks and covers the other with its tail, and deaf to those magic sounds, does not go out to the man who is charming him.
Of a similar nature are the men of this world, who close one ear with earthly desires. The other they block with their deeds, lest they hear the voice of the Lord saying: ‘Whosoever he be of you that foresaketh not all that he hath, he cannot be my disciple or servant’ (see Luke, 14:33). Asps do no more than merely close their ears. Men of this world blind their eyes lest they see heaven and are reminded of the works of the Lord.
The dissa is a kind of asp, called situla in Latin, because those it bites die of thirst, sitis. There is a kind of asp called ypnalis, because it kills you by sending you to sleep. It was this snake that Cleopatra applied to herself, and was released by death as if by sleep. The emorrosis is an asp, so called because it kills by making you sweat blood. If you are bitten by it, you grow weak, so that your veins open and your life is drawn forth in your blood. For the Greek word for ‘blood’ is emath. The prester is an asp that moves quickly with its mouth always open and emitting vapour, as the poet recalled like this: ‘The greedy prester that opens wide its foaming mouth’ (Lucan, Pharsalia, 9, 722). If it strikes you, you swell up and die of gross distention, for the swollen body putrefies immediately after.
The spectaficus is an asp which, when it bites a man, destroys him, so that he turns entirely into fluid in the snake’s mouth. The cerastis, is so called because it has horns on its head like a ram’s. For the Greek word for ‘horns’ is ceraste. It has a set of four small horns and, displaying them, it persuades animals that they are good to eat, then kills its prey; for it covers its entire body with sand, so that no trace of it shows, except the part with which it catches the birds or animals it has attracted. It bends more than other snakes, so that it seems to have no spine.