The plant called “nymphæa,” owes its name, they say, to a Nymph who died of jealousy conceived on account of Hercules, for which reason it is also known as “heracleon” by some. By other persons, again, it is called “rhopalon,” from the resemblance of its root to a club.[663] * * * * and hence it is that those who take it in drink become impotent for some twelve days, and incapacitated for procreation. That of the first quality is found in Orchomenia and at Marathon: the people of Bœotia call it “madon,” and use the seed for food. It grows in spots covered with water; the leaves[664] of it are large, and float upon the surface, while others are to be seen springing from the roots below. The flower is very similar to a lily in appearance, and after the plant has shed its blossom, the place of the flower is occupied by a head like that of the poppy. The stem is slender, and the plant is usually cut in autumn. The root, of a swarthy hue, is dried in the sun; garlic[665] manifests a peculiar antipathy to it. There is another[666] nymphæa also, which grows in the river Peneus, in Thessaly: the root of it is white, and the head yellow, about the size of a rose. CHAP. 38.—TWO VARIETIES OF EUPHORBIA: FOUR REMEDIES. THE CHAMELÆA. In the time, too, of our fathers, King Juba discovered[667] a plant, to which he gave the name of “euphorbia,” in honour of his physician, Euphorbus, the brother of the same Musa, whom we have mentioned[668] as having saved the life of the late Emperor Augustus. It was these brothers who introduced the practice of douching the body with large quantities of cold water, immediately after the bath, for the purpose of bracing the system: whereas in former times, as we find stated in the works of Homer[669] even, it was the practice to wash the body with warm water only. With reference to euphorbia,[670] there is a treatise still in existence, written upon it by King Juba, in which he highly extols its merits; he discovered it growing upon Mount Atlas, and describes it as resembling a thyrsus in appearance, and bearing leaves like those of the acanthus.[671]