Amenorrhœa, permanent or transient abnormal lack of the menstrual flow, may depend upon anatomical changes in the genital organs, upon incomplete development or absence of the uterus and the ovaries, upon enduring or transient defective nutrition or upon atrophy of these organs, or upon parenchymatous disease of the ovaries; or it may be due to functional disturbances of ovarian activity, itself dependent upon changes in the nervous system, upon constitutional diseases, or upon general nutritive disturbances in the body. Among the latter conditions must be especially mentioned chlorosis, obesity, diabetes, chronic alcoholism, and morphinism, myxoedema, exophthalmic goitre, etc. The amenorrhœa that occurs at the time of the menarche has already been described in connection with the symptomatology of that period. If in cases of amenorrhœa the ovaries continue to perform their functions, we frequently witness severe and painful menstrual molimina, occurring periodically at the times when the flow might be expected, but fails to appear. In cases of atrophy of the uterus and the ovaries, we see complete and permanent amenorrhœa without any discomfort. As a kind of vicarious menstruation, in certain cases of amenorrhœa, we see hæmorrhages into the vitreous body or conjunctival hæmorrhages; also, as more extensive disturbances of the visual organs, interstitial keratitis, disseminated choroiditis, intermittent amaurosis, acute retrobulbar neuritis, amblyopia, and limitation of the field of vision.