I examined 140 women in whom the heart and the vascular system were normal, during a number of successive menstrual periods, and in 12 of these women, either at the commencement or during the course of the flow, I observed an increase in the frequency of the heart to the extent of from 12 to 28 beats per minute; in young girls, a systolic murmur was sometimes audible during menstruation, but was inaudible in the intermenstrual intervals. In all these persons, menstruation was regular; there was no abnormality in respect either of the duration or of the quantity of the flow. The heart in these cases was, therefore, affected by the normal menstrual process. A remarkable illustration of the alleged influence of menstrual disturbances on the pulse is reported by _de Villeneuve_, who states that Chinese physicians, being accustomed to feel the pulse in many different arteries, are able, by a comparison of the characters of the pulse in the two arms, to determine whether a woman menstruates regularly or irregularly. Many women and girls show well-marked menstrual molimina, uneasy or actually painful local sensations in the genital organs, sacrache, painful uterine contractions, and disturbances of the general constitutional state, which are dependent upon menstrual congestion of the pelvic organs, upon local engorgement; sometimes such symptoms are the result of uterine contractions caused by hyperæmia of the uterus, and these cases often take a paroxysmal form. Important disturbances of the general constitutional state result from sudden suppression of the normal menstrual flow, such as may be the effect of a severe chill, of sudden mental impressions, even of errors in diet or the use of certain drugs, and may sometimes follow artificial withdrawal of blood.