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XLVI] soothing treatment by lead lotion, or an ichthyol or hazeline ointment is desirable in such cases. A tincture of the leaves of Cassia alata painted on, or vigorous rubbing with the crushed leaves themselves, is equally successful. If these fail, chrysophanic acid ointment, 20 gr. to the ounce of vaseline, rubbed in twice a day till a slight erythema shows at the edge of the diseased patch, is almost invariably successful. When prescribing chrysophanic acid the physician must be careful to inform the patient of its staining effect on clothes; to warn him to stop its use so soon as the erythematous ring shows; and to be careful not to apply the ointment to the face. A writer in the ''Indian Med. Gaz.'' (Jan., 1898) strongly recommends the application of glacial acetic acid. It cures, he affirms, with, at most, two applications. The smarting its use entails is relieved by laying a lump of ice in a handkerchief on the part. Castellani and Chalmers recommend an ointment of resorcin ʒi, salicylic acid gr. x, lanolin, vaseline, āā ʒiv, to be applied twice a day. For the ringworms of the thick-skinned natives linimentum iodi freely applied, and of double strength, is the best and a most efficient remedy.

Prophylaxis.—The various forms of crutch dhobie's itch may be avoided by wearing next the skin short cotton bathing-drawers and changing them daily; at the same time powdering, after the daily bath, the axillæ and crutch with equal parts of boric acid, oxide of zinc, and starch.

Definition.—A form of body ringworm, until lately peculiar to certain Eastern oceanic tropical climates, produced by a trichophyton, and characterized by a concentric arrangement of closely set rings of scaling epidermis.

Geographical distribution.—This peculiar form of epiphytic disease is strictly confined to warm climates. It is principally met with in the Eastern Archipelago and in the islands of the South Pacific, although it has been found to extend westward as