Of the echios there are two kinds; one753 of which resembles pennyroyal in appearance, and has a concave leaf. It is administered, in doses of two drachmæ, in four cyathi of wine. The other754 kind is distinguished by a prickly down, and bears small heads resembling those of vipers: it is usually taken in wine and vinegar. Some persons give the name of “echios personata”755 to a kind of echios with larger leaves than the others, and burrs of considerable size, resembling that of the lappa.756 The root of this plant is boiled and administered in vinegar. Henbane, pounded with the leaves on, is taken in wine, for the sting of the asp in particular.