Whenever a patient presents such symptoms an examination should be insisted upon. It will generally reveal a smooth, soft, and fluctuating tumor, projecting externally if the case be one of imperforate hymen, or higher up if the vagina be occluded. If the uterus has become distended, {185} there will be a round, smooth, elastic tumor above the pubes. Diagnosis will be more or less difficult according to the seat of the obstruction. Cases of imperforate hymen may be readily diagnosed by sight, if touch and the history are not sufficient. When the occlusion is deeper, the patient should be placed under the influence of an anæsthetic. By one finger in the rectum and the thumb in the vagina, and a sound in the bladder, the seat and extent of the obstruction may be determined. Should it be necessary, the urethra may be dilated and a finger passed into the bladder in order to make a diagnosis. Rectal exploration is of great assistance in discovering the uterine enlargement and its character. Scanzoni calls attention to the difference in the cervix when the atresia is at the internal or external os. In the latter case the cervix will be obliterated; in the former, it will be unchanged. With a perfect vagina and a cervix of this character retention may be taken for an early pregnancy, especially as it is not uncommon for sympathetic mammary symptoms and gastric troubles to be present. Time will demonstrate the nature of the case if a diagnosis cannot be made at once. The age at which the menstrual flow is established varies greatly. The average age of puberty in this country, as appears from Emmet's tables made up of 2330 cases, is 14.23 years, and these are believed to be the only American statistics. A close correspondence may be noted between this and the statistics of the four largest cities of France, which give 14.26 as the average. But that it is not unusual for the appearance of menstruation to be delayed is shown by the fact that of the above 2330 cases, 288 only menstruated at sixteen years and 254 more between that age and twenty-three. The circumstances which may influence, within physiological limits, the appearance of menstruation should be considered in connection with cases of this kind. Climate and social position are the principal ones. The epoch of puberty descends in the scale of age in proportion to the average height of the temperature of various countries, and vice versâ. Social position and city life show a marked effect in hastening puberty as compared with the simpler manners and plainer life of rural populations. It amounts to an average of something over a year, and is explained by the influence of enervating and luxurious habits, of light reading and the drama, the chief subject of both being the grand passion, but especially of a freer intercourse between, and the co-education of, the sexes, and the greater extent to which music is cultivated and enjoyed.