THE GENERATIVE APPARATUS 375 



period there are found signs of a gradually increasing vitality of the internal 

 organism, that rapidly reduces during the bleeding. In the seven or nine 

 days immediately before menstruation the blood-pressure increases, it falls 

 rapidly with the beginning of the flow, and reaches its lowest value at the 

 close of the period. With this variation in blood-pressure are associated 

 variations in the erythrocyte count. In the premenstrual period the ery- 

 throcyte count may lie i to i^ millions higher than toward the end of 

 menstruation. It is very possible indeed that just as in tetany, these 

 variations in the erythrocyte count are to a great degree the expression of an 

 increased or diminished tonus of the vessels; for which view speaks also the 

 careful blood-pressure measurements. In connection with it may stand 

 too the strong permeation of many organs with blood. Moreover in the 

 premenstrual period there is found a higher level of bodily temperature that 

 becomes prominent especially in latent diseases (Reinl). On the day pre- 

 ceding and the day following menstruation the temperature is the lowest. 

 In many individuals there may also be demonstrable, in the premenstrual 

 period, a slight neutrophilic hyperleucocytosis and a slight heightening of 

 the coagulability of the blood. Also the respiratory volume is often raised 

 in the premenstrual period, while it is slightly decreased during menstrua- 

 tion (L. Zuntz). Many of the manifestations detailed seem to me to point 

 to an increased function of the chromaffin tissue. With this may be con- 

 nected the observation that in the premenstrual period the glycosuric ac- 

 tion of adrenalin is heightened. Moreover there is found an increase in 

 reflex excitability and often a higher mental alertness and capacity, while 

 during menstruation there often occurs a certain mental obtuseness. Known 

 for a very long time is the swelling of the thyroid gland in the premenstrual 

 period (struma antemenstrualis, Heidenhain). It is further stated that 

 before rut and in the premenstrual period the suprarenal cortex increases in 

 size. Also the interstitial glands show the same behavior during this period, 

 apparently also does this hold true for the glandular hypophysis. At least 

 such a conclusion seems suggested by the similar alterations of these ductless 

 glands during pregnancy; perhaps there is also found in the premenstrual 

 period an increased growth of any beard that may be present (Halban). 

 Finally it is known that the mammary glands often swell slightly, and in 

 rare cases even in the virgin may secrete a slight amount of colostrum. 

 Further the nipples often show an increased erectibility and are painful. 



What now is the cause of this rhythmically occurring menstrual wave? 

 Pfluger developed a theory that monthly ovulation leads by reflex paths to a 

 hyperemia of the pelvic organs, thereby causing menstruation. Pfluger's 

 law has been made untenable by the knowledge that the influence of the 

 ovaries in the organism is independent of the nervous system and depends 

 on the giving off of substances to the blood-path. Hence it must be modified 

 to state that the influence of the internal secretion of the generative apparatus 



