2,998, that is 66.006 per cent., in whom the composition was regular. 1,544, that is 33.994 per cent., in whom the composition was irregular. and among the latter the discharge was Scanty and for the most part pale in 511; that is 12.250 per cent. Profuse or profuse and coagulated in 838; that is 18.428 per cent. Variable in 196; that is 4.315 per cent. Investigation regarding the individual variations that occur in this respect among women, showed that blondes usually menstruate more profusely than brunettes, and that in the former also the duration of the individual periods is longer. The loss of blood must be considered less in respect of its absolute quantity than in respect of the effect which continued observation shows its loss to have upon the organism. If the loss of blood continues to have an effect after the flow has ceased, if a woman recovers but slowly, or even fails to recover fully from one loss before another begins, if symptoms of increasing anæmia become apparent, the bleeding must be regarded as a pathological perversion of normal menstruation. Pathological is it also if the menstrual flow does not exhibit the normal slowly rising and slowly declining curve, but sets in profusely, ceases or almost ceases for a time, and then again suddenly recurs. In some cases the flow is not profuse, but lasts for a long time, and owing to this long duration it has a debilitating effect, especially in anæmic and chlorotic individuals. As a rule, in normal menstruation, the admixture of the alkaline cervical mucus suffices to keep the menstrual discharge fluid and to prevent the formation of fibrin. On the other hand, the discharge of coagulated masses of blood will alone suffice to indicate an abnormally free and rapid flow of blood. The commonest type of menstruation is the more or less regular recurrence of the flow at intervals of twenty-eight days. Variations in this respect are, however, very frequent, and are dependent upon constitution, position in life, and race. In general it may be said that in persons of strong constitution, the type of menstruation is much more regular, than in persons of a weakly, delicate constitution; that in vivacious, ardent natures the menses more readily anticipate the expected period of their return, whereas in those of a flaccid, lymphatic temperament a retardation is more likely to occur; and that amongst women of the upper classes of society the type of menstruation is far more frequently irregular than amongst women of the working classes and amongst countrywomen. Whereas in many women the regularity of the menstrual rhythm is so precise that the flow recurs, not merely at regular intervals of twenty-eight days, but even time after time at exactly the same hour of the day—in other cases the interval between two periods may vary from twenty-one to thirty days.