In two cases in which the menstrual flow was in abeyance, _Heitzmann_ observed affections of the skin. In one of these, a young woman aged twenty who had not yet begun to menstruate, there appeared every four weeks isolated papules surrounded by a bright red areola, itching so violently that scratching resulted. In the other, macules the size of a lentil, of a light red or dark red color, appeared, and lasted two or three days; when menstruation became regular, fresh crops no longer formed. _Schauta_, in a case of chronic oöphoritis, observed the regular recurrence of urticaria at each successive menstrual period. The suffering being very great, the rest at night being greatly disturbed during the periods of eruption, and the patient’s general health declining more and more in consequence, extirpation of the ovaries was undertaken, and the operation resulted in a complete cure. _Schauta_ further observed that in cases of obstinate skin-affections of unknown causation occurring in persons of the female sex, some disorder of the genital organs was nearly always present; moreover, in many of these cases, as soon as the genital disorder was cured by appropriate measures, the skin-affection disappeared spontaneously and without any further treatment. He had been able to collect twenty-six cases of this nature, in which an indubitable connection obtained between disease of the skin and disease of the reproductive system. The forms of affection of the genital organs chiefly noticed in this association were, retroflexion and retroversion of the uterus, erosion and ectropium or eversion of the cervix (chronic cervical catarrh), chronic endometritis, oöphoritis, and salpingitis, and finally with especial frequency uterine myomata; the skin-diseases observed were, acne, eczema, disorders of pigmentation, psoriasis, lichen, and urticaria. During menstruation we observe not infrequently a number of changes in the skin, such as hyperidrosis, acne, seborrhœa, erythema, and the form of dermatitis known as erysipelas of menstruation; sometimes also effusion of blood into the skin as a form of vicarious menstruation, and peculiar forms of cutaneous œdema. In many women during menstruation the secretion of sweat is markedly increased every month; in exceptional cases, menstruation is vicariously replaced by profuse sweating. In association with menstruation we frequently observe excessive secretion of the sebaceous glands, especially of those of the hairy scalp. Often urticaria manifests itself as a recurrent menstrual eruption. In cases of scanty menstruation and of amenorrhœa, discoloration and excessive pigmentation of the skin may occur, sometimes taking the form (as also in pregnancy) of chloasma uterinum. Sometimes also in these cases the formation of dark rings round the eyes, already seen in slighter degree as an accompaniment of normal menstruation, is excessive.