Bats' blood has all the virtues of a depilatory: but if applied to the cheeks of youths, it will not be found sufficiently efficacious, unless it is immediately followed up by an application of verdigrease or hemlock-seed; this method having the effect of entirely removing the hair, or at least reducing it to the state of a fine down. It is generally thought, too, that bats' brains are productive of a similar effect; there being two kinds of these brains, the red and the white. Some persons mix with the brains the blood and liver of the same animal: others, again, boil down a viper in three semisextarii of oil, and, after boning it, use it as a depilatory, first pulling out the hairs that are wanted not to grow. The gall of a hedgehog is a depilatory, more particularly if mixed with bats' brains and goats' milk: the ashes, too, of a burnt hedgehog are used for a similar purpose. If, after plucking out the hairs that arc wanted not to grow, or if, before they make their appearance, the parts are well rubbed with the milk of a bitch with her first litter, no hairs will grow there. The same result is ensured, it is said, by using the blood of a tick taken from off a dog, or else the blood or gall of a swallow.

(15.) Ants' eggs, they say, beaten up with flies, impart a black colour[1] to the eyebrows. If it is considered desirable that the colour of the infant's eyes should be black, the preg- nant woman must eat a rat.[2] Ashes of burnt earth-worms, applied with oil, prevent the hair from turning white.