Galen gives a very full account of the nature and treatment of herpes. According to him the complaint arises from yellow bile separated from the blood and fixed in a part. When it is thickish it ulcerates the skin down to the bone, and forms the disease called by Hippocrates _herpes exedens_. But if thinner, it only burns as it were the surface, when it is called by the generic term of herpes. Of the other two varieties, the one, as has been said, is called _exedens_, and the other _miliaris_, because it is attended with many small bullæ (phlyctænæ) like millet-seeds. As our author’s treatment is entirely derived from him we shall not enter into any detailed exposition of his practice. We may mention, however, that he decidedly recommends purgatives for proper herpes. When the ulceration is of a malignant nature and attended with putridity it requires the most acrid medicines, and such as in power resemble fire, namely, misy, chalcitis, arsenic, quicklime, and sandarach. For, he adds, these medicines burn like fire, and often when they fail, we must have recourse to fire itself. Aëtius gives an accurate account of herpes, but it is professedly borrowed from Galen. Like him he divides the disease into three varieties, the herpes proprius, the herpes exedens, and the herpes miliaris, the last being characterized by an eruption of vesicles (phlyctænæ). We shall here notice what Dr. Bateman says respecting this division of herpes:—“The ancient division of herpes into three varieties, miliary (κεγχρίας), vesicular (φλυκταινώδης), and eroding (ἐσθιόμενος), may be properly discarded, for there appears to be no essential difference between the first two, which differ only in respect to the size of the vesicles.” This is evidently an incorrect account of the ancient division, in which no distinction was made between the herpes miliaris and the herpes phlyctænodes. Palladius makes mention of only two varieties of the disease, namely, the proper, and the eroding herpes. (De Febribus 2.) Leo briefly refers to Galen’s account of the disease (vii, 3.) Actuarius mentions only the proper herpes, and the herpes miliaris. This is, perhaps the best division of any, as the herpes exedens is evidently a disease of a very different nature from the other varieties. The Pseudo-Dioscorides recommends strong stimulant applications containing sori, misy, sulphur, onions, &c. Avicenna seems to confound herpes with myrmecia, which detracts from the value of his account of it. (iv, 3, 1, 7.) Rhases describes separately the formica miliaris or herpes miliaris, and the herpes esthiomenos or exedens. For the former he recommends astringent applications, for the latter strong caustics. In his ‘Continens’ he directs the herpes miliaris to be treated with cholagogues and astringent applications. Serapion in like manner describes two varieties of the disease, but his account of it contains nothing particularly interesting.