Introduction During the past three years a very general interest has arisen, especially in the United States, in tumors of the neuromyo-arterial glomus, which are small growths characterized clinically by severe pain, often of a paroxysmal nature. It has been very generally agreed that these must be one form of the painful subcutaneous tubercle first so designated by William Wood of Edinburgh in 1812, although previously described by Cheselden, Valsalva, Morgagni, Bisset, Pearson and others in the eighteenth century. But this is not the only lesion which may be called painful subcutaneous tubercle or tuberculum dolorosum as the continental writers named it. In 1854 Virchow first reported that a group of small tumors composed chiefly of smooth muscle and involving the skin of the thoracic wall in the neighborhood of the areola of a thirty-two-year-old man caused exactly the same type of paroxysmal pain as did tubercula dolorosa. Although Verneuil described a case of multiple cutaneous leiomyomas in a cadaver in 1858, and Duhring in 1873 and Kosinski in 1874, cases of undoubted multiple leiomyomas which they mistook for neuromas, the disease did not become well known until 1880, when Besnier published his comprehensive paper. After that, case reports multiplied so that now there are at least 132 cases of multiple dermatomyomas in the literature and the disease is well known in all parts of the world. During the years after Virchow's paper, case reports of solitary superficial leiomyomas began to make their appearance. The earlier cases were all painless tumors—Förster's, 1858, in the scrotum; Aufrecht's, 1868, in a subcutaneous vein in the side of the foot; Klebs', 1869, in the neck, Challand's 1871, in the labium majus and in the scrotum; Sokolow's, 1873, in the nipple. The first reported case of leiomyomatous tuberculum dolorosum occurred in the subcutaneous tissues of the poet Stranberg's finger and was described in 1873 by Axel Key. In the year 1884 Malherbe was able to publish descriptions of five solitary painful leiomyomas which had come to his attention during the preceding nine years. Since these were the only cases of tuberculum dolorosum that he had ever seen, he supposed that the leiomyoma was its only form.