Wart or warty growths are to be differentiated by attention to their history and course. Long-continued observation may be necessary before a positive opinion is warrantable. The appearance of any tendency to crusting, to break down or ulcerate is significant of epitheliomatous degeneration. In lupus vulgaris the deposits are peculiar and multiple, the ulcerations are of different character, the tendency to scar-formation constant; and, with few exceptions, it has, moreover, its beginning in childhood or early adult life. #What factors are to be considered in giving a prognosis in epithelioma?# The variety, extent, and rapidity of the process. The superficial form may exist for years, and give rise to no alarm; whereas the deeper-seated varieties are always to be viewed as serious, and are, indeed, often fatal. Involving the genitalia, its course is often strikingly rapid. Relapses, after removal, are not uncommon. #What is the special object in view in the treatment of epithelioma?# Thorough destruction or removal of the epitheliomatous tissue. #How is the destruction or removal of the epitheliomatous tissue effected?# By the use of such caustics as caustic potash, chloride-of-zinc paste, pyrogallic acid, arsenic, and the galvano-cautery; and by operative measures, such as excision and erasion with the dermal curette, and by the _x_-ray. (See treatment of lupus vulgaris.) In small lesions the use of an arsenical paste is a most admirable method of treatment, although somewhat painful. The paste is made of one part powdered acacia and one to two parts arsenious acid; at the time of application sufficient water is added to make a paste. This is applied thickly, and a piece of lint superimposed. A good deal of pain and inflammatory swelling ensue; at the end of twenty-four hours the part is poulticed till the slough comes away; the ulcer is then treated as a simple ulcer, under which healing takes place. Occasionally a second application is found necessary. Upon the whole, the best method in the average case is to curette thoroughly, and supplement with momentary cauterization, with caustic potash, or with several days' use of the pyrogallic acid ointment. During the healing process, short exposures to the Roentgen ray--about every three to five days--is good practice. The degenerative changes in the beginning of scurfy, seborrh[oe]ic spots or patches seen in old people can frequently be lessened or wholly stopped by the daily application of an ointment containing 5 to 10 per cent. of sulphur and 2 to 5 per cent. of salicylic acid. #What can be said of the value of the x-ray in epithelioma?#