COMMENTARY. There can be little or no doubt that the purple violet of Dioscorides is the _Viola Odorata_. On the violet, see a most interesting disquisition by Celsius (Hierobotanicon in voce Dudaim); also Sprengel (R. H. H.) Dioscorides calls it refrigerant, and recommends it as an external application in ardor of the stomach, inflammation of the eyes, and prolapsus ani; and mentions, that it had been taken internally in quinsy and epilepsy of children. (iv, 120.) Galen merely recommends it externally in the same cases as Dioscorides. The Arabian authorities extend the use of this article. Thus, Avicenna recommends it in heat of the stomach, both internally and externally; in a syrup for coughs, pleurisies, and other affections of the lungs; in pains of the kidneys as a diuretic, and as a cholagogue. (ii, 2, 715.) See also Rhases (Cont. l. ult. 3, 21), and Ebn Baithar (i, 170.) Serapion, on the authority of Aben Mesuai, says further of it that it is laxative in doses of from three to seven drachms. (De Simpl. 141.) Ἰὸς, Ærugo, _Verdigris_, has a bitter quality to the taste, being discutient, cathartic, and corrosive, not only of soft but also of hard flesh; but by mixing a little of it with much cerate, one may render the medicine detergent without pungency. * * * * * COMMENTARY. That it was the _Ærugo Æris_, or Verdigris, seems indisputable. The scraped verdigris (ἰὸς ζυστὸς) was the common kind, and the name is still retained in the modern Greek Pharmacopœia (61.) Hippocrates, Dioscorides, Pliny, and Galen recommend verdigris in complaints of the eyes. Dioscorides describes very minutely the process for preparing verdigris, which is not very unlike that which is now practised in France. He also makes mention of another species, namely, the _Ærugo Scolecia_, with which we are now unacquainted. He gives an interesting account of the cases in which it is applicable. (v, 92.) Galen also writes of it with great precision. He says, when lightly applied it relieves fungated sores; and when diluted with cerates, it cleanses them. (De Simpl. ix.) The other Greek authorities give much the same account of it. The Arabians treat fully of the two kinds, which they call _Ærugo rasilis_ and _subtilis_, but borrow almost all their information from Dioscorides and Galen. Like the Greek authorities, they apply it principally in intractable ulcers and in diseases of the eyelids. See Avicenna (ii, 2, 739), and Serapion (De Simpl. 383); Haly Abbas (Pract. ii, 44); Ebn Baithar (i, 540.) Ἱππόκαμπος, Hippocampus, is a sea animal, the ashes of which when burnt thicken the hair in alopecia, along with liquid pitch. * * * * * COMMENTARY. It is, indisputably, our _Syngnathus Hippocampus_. Ælian relates that it has proved useful in cases of hydrophobia. (Hist. Anim. xiv, 20.) Our author borrows from Dioscorides (ii, 3.) The Arabians do not treat of it. Ἱππολάπαθον,