Serpentum et Draconum Historiae

Conversely, as autumn approaches, all the vegetable spirits of this balsam return to their subterranean channels as if to their matrix; whither the serpents, directing their journey once more, return to their crypts, so that they may again enjoy this spiritual nourishment. And Quercetanus confesses that he learned this not from the serpents themselves, but from their effects: for indeed, snakes dwelling underground during the wintertime are not only imbued with the aforementioned radical balsam so that, upon the arrival of spring, they shed their old slough and wander about as if young, but they also acquire the faculty of removing leprosy—a virtue which nature has not bestowed upon other remedies. And because someone might doubt that many other animals, besides serpents, inhabiting the earth's caverns in winter could share in this radical balsam, Quercetanus responds that this property was assigned by nature to serpents alone, just as nature has granted the antithora the power of extinguishing the poison of the thora. Furthermore, because someone gifted with a sharp wit could doubt why the efficacy of this balsam does not remove the poison from serpents and expel it, he replies again that in honey-bees, too, a sting is observed.

Exercit. 189.

Cardanus, in his History of Subtlety, asserts that the slough is cast off by serpents in the spring due to dryness, which they contract from winter fasting, and he confesses that it happens to them as it does to humans suffering from elephantiasis, whose skin, dried from the vapor of corrupted humor, becomes elevated. Scaliger, however, in his Exercitations against Cardanus, writes that this can by no means proceed from the dryness of the animal, for indeed, the spotted lizard (stellio) sheds its old age while partaking of no dryness at all. Moreover, trees are far drier, and yet they change no bark. Likewise, cantharides are judged to be the driest among insect animals, yet they do not leave behind their first sloughs when the year turns. In resolving this difficulty, the opinion of Grevinus pleases us more, who does not believe that the renewal of snakes is a genuine skin at all, but rather a slough born of mucus and filth, collected like moss in their hiding places around the animal's body and dried out, which they subsequently leave behind when they emerge from their caverns in the spring and rub themselves against narrow places.

Lib. 1. de Venen.

True opinion concerning the slough of snakes.

Besides these things, serpents are said to have procured for themselves a long life from nature, and many think this stems from the cast-off skins. However, this is to be attributed to the excellent constitution of the liver, since it is diligently purged of bilious excrement, as a large quantity of this excrement is contained in the gallbladder. Yet one might hesitate if the cause of a long life is attributed to the deprivation of bile—as happens to deer, according to Mercurialis—for then it would not be asserted that serpents are longer-lived due to a redundancy of bile. We discuss this doubt together with the Philosopher, while we assign the liveliness of this animal to a sound and suitable constitution of the liver, since the liver is also diligently purged of even the smallest portion of bilious humor, while the bile of serpents, not flowing through the veins, does not harass their viscera and body. For such a poison flows continuously down to that membrane covering their teeth, so that it is prompt and ready for any strike they make. Indeed, since it does not pass through the veins, these animals are not only longer-lived but are also immune to many afflictions to which other animals are prone due to the excessive abundance of this excrement entering their veins. Moreover, according to the opinion of some, serpents are said to be of longer life because they are very sparing in their diet; for if they ate in the manner of other animals, their weak heat would be extinguished, and they would perish immediately. But this history is pressed by another difficulty: since, if snakes are filled with such weak heat, they could not lead long years. It must be noted that serpents, in comparison to other beasts, possess this innate heat proportioned to their nature, and tenaciously coupled with a viscous radical moisture, in which it is preserved so well that, due to its viscosity, it cannot vanish so quickly; therefore, these animals enjoy the long use of light. This seems to be clearer in plants that are green with a perpetual crown under the meridian sun: for indeed, these do not shed their leaves in the wintertime due to the viscous humidity in which their heat resides, which cannot recur to the roots at that time, as is wont to happen with other kinds of plants.

Lib. 1. var. lect. cap. 23.

Serpents are of longer life.

Why some plants do not shed leaves in winter.

There is added the watchfulness which many deem to be proper to serpents, for which reason the poets fabled that the garden of the Hesperides was guarded by serpents. Alluding to this, Martial, discussing a certain gift of apples, sang thus: