62 



THE PHYSIOLOGY OF REPRODUCTION 



about half the month, when it rises to half a degree above the mean. 

 It falls below the mean line just before the onset of menstruation, 

 during which it remains about half a degree below. Similar results 

 were obtained by Heiul, Ott, and Giles, 1 but Vicarelli z and certain 

 other authors have recorded an increased temperature during 

 menstruation.-' 5 Zuntz, 4 however, as a result of more recent experi- 

 ments, says that there is a regular lowering of the temperature 

 throughout the menstrual period, after which it rises to the normal. 

 Stevenson states also that the curve of urea excretion follows 



25 



Fio. 1. Diagram illustrating the " Wellenliewegung" hypothesis. The 

 curve AB represents the varying intensity of the vital processes 

 during the twenty-eight days of the menstrual cycle. The numbers 

 between m and n represent the days occupied by menstruation. 

 (From Sellheim.) 



a similar course to the temperature curve, and that, speaking 

 generally, there is an increase in metabolism coincident with the 

 time of development of the uterine mucosa. There is, however, no 

 doubt much truth in von Xoorden's criticism "' that the "menstrual 

 wave" hypothesis has given occasion to many premature conclusions 



1 (iiles, "The f'ydical or Wave Theory, etc.," Tr>in.. nhxh't. ,S'<-., London, 

 vol. xxxix., 1*97. 



- Vicarelli, '' La temperature de 1'ute.rus dans M-S diviT.se> conditions 

 physiolo<,'i<|iu'>," .!/<//. //<//. </- /Hi,/., vol. xxxii., IMH). 



; Sfameni, ''Influence de la menstruation sur la i|iiantit<- d'ht'iuo^lol)inr," 

 .\r<-h. lt<il. ,/,- AW., vol. xxxii.. !*!)'.. 



1 Zuntz L. , " Kintluss der Ovarien auf den StoH'werlisd," .\, <!,. /'. <!,/nid-., 

 vol. Ixxviii.. HXM;. 



" Von Noord-n. M>'tiilii>li.tiii an'/ /'/<///?/ J/< //<///< -(Knglisli Translation), 

 vol. i., London, I'.niT. 



