Ringworm of the scalp is a common disease of childhood, particularly in England, France and the United States. Ringworm of the bearded region in men and of the nonhairy parts in adults is not unusual, while the same disease affecting the nails is probably more common in adults than in children. It is therefore strange that ringworm of the scalp in adults should be such a decided rarity, at least in Europe and America. The first report of ringworm of the adult scalp in the United States was made by Cantrell1 in 1896. Since then, only three other cases have been reported in this country in which the diagnosis was confirmed by the microscope. Of the three cases which form the basis of this communication, two were those of patients from the service of one of us at the Harlem Hospital and the third from the service of Dr.