Alsaharavius describes three varieties of _morphea_. 1st. The morphea terrestris, which is attended with furfuraceous scales on the skin, and tingling. This is evidently the psora of the Greeks. 2d. The morphea alba, which consists of a more superficial whiteness of the skin than the _albaras_ (leuce): this is the alphos albus. 3d. The morphea nigra, is like the former, only that the colour is black. This must be the alphos niger. All these affections he treats upon much the same principles as the Greeks, namely, by evacuants, and stimulant applications to the skin, such as sulphur, hellebore, &c. _Albaras_ he describes as a deep-seated whiteness of the skin, and directs us to prick the skin with a needle, and if it does not bleed the disease is to be set down as incurable. This, of course, is the leuce of the Greeks. He treats it upon much the same principles as the morpheæ. He appears not to make any distinction between the leuce and the lepra. Rhases describes the lepra of the Greeks by the term _impetigo_; alphos albus by that of _morphea_ alba; alphos niger by that of _morphea_ nigra; and leuce by that of _albaras_. There is nothing very particular in his treatment of leprosy. It may be worth while to mention, however, that he strongly recommends leeches to the affected part, at the commencement. Scabies, he says, is formed by a salt diet, old wine, and neglect of the bath. For the cure of it, he recommends bleeding, purging, and various external applications, some of which contain quicksilver, nitre, vinegar, and the like. In his ‘Continens’ he gives a full account of these diseases, upon the authority of preceding writers. He gives the names of _baras_ to lepra, and _morphea_ alba to alphos. He recommends stimulant applications containing cantharides, nitre, with vinegar, &c. He says that he had found a mixture of sal ammoniac and oil of eggs an excellent application. It will be remarked that the leuce of the Greeks, the leuce and fourth species of impetigo of Celsus, and the albaras of most of the Arabians, are the same as the _lepra vulgaris_ of Drs. Willan and Bateman; that the alphos of most of the Greek authorities and of Celsus, and the morphea alba of most of the Arabians, correspond to the _lepra alphoides_ of our English nosologists; that the melas, alphos niger, and common lepra of the Greeks, Celsus’ third species of impetigo and his melas, and the morphea nigra and impetigo of most of the Arabian translators, apply to the _lepra nigricans_ of our modern arrangement; and that the psora of the Greeks, Celsus’ second species of impetigo, and the scabies of Octavius Horatianus, and of most of the Arabian translators, comprehend both the _psoriasis_ and _scabies_ of Willan and Bateman. Since many of the ancient authorities speak of _scabies_ as being infectious, they must have applied the term to the true itch, with which it is not likely, as Rayer maintains, that they were wholly unacquainted.