_Galen_[97] distinguishes between λειχὴν ἁπλοῦς and λειχὴν ἄγριος (simple _lichen_, and malignant _lichen_) in his enumeration of Skin-diseases, and still more plainly in another place[98] he says: “λειχὴν is likewise a Skin-disease; there are two forms of it, ὁ μὲν ἥμερος καὶ πρᾳότερος, ὁ δὲ ἄγριος καὶ χαλεπώτερος (the one benignant and milder, the other malignant and more serious). But in both of them minute scales are detached from the skin, and the part of the skin underneath the scales is reddened and almost ulcerated. The affection arises from a salt phlegmatic humour (φλέγματος ἁλμυροῦ) and yellow gall, hence the scales fall from the skin as in glazed pottery-ware (? ἐπὶ τῶν ἁλμῶν τῶν κεραμίων). The affection is cured by internal phlegmagogues and external embrocations.” We have already on p. 139. above, in the footnote on ἄγριος (wild, savage) and χαλεπός (hard, harsh), noted how these words are used with special reference to the vice of paederastia, but they are also applied generally to the vice, the different forms of which we have been examining here. This follows from _Plato_[99] and _Plutarch_[100], at any rate so far as ἄγριος is concerned, which indeed we may conveniently render by _vicious_. The original meaning being overlooked, λείχην and λιχὴν had been taken as synonymous,—possibly the Latin _lichenos_ first led to the mistake; then naturally enough an appropriate epithet was sought, to signify the _lichen_ which was the result of licking in a vicious fashion. But this according to the already existing mode of speech could be nothing else than ἄγριος[101] again,—λειχὴν ἄγριος, with which λειχὴν ἁπλοῦς, _lichen insons_, (simple, innocent _lichen_) was naturally contrasted.