84 THE PHYSIOLOGY OF REPRODUCTION 



others have ascribed the breaking down of the vessel-walls to 

 fatty degeneration, but this has been denied by Moricke, 1 and 

 more recently by Findley, 2 while Leopold has described the 

 appearance of the fatty degeneration as a result rather than a 

 cause of haemorrhage. 



After the extravasation of blood, the corpuscles tend 

 to become aggregated in lacunae which lie beneath the superficial 



FIG. 8. Section through mucosa of human uterus showing extravasation 

 of blood. (From Sellheim.) 



epithelium. These lacunae are the sub-epithelial hsematomata of 

 Gebhard, 3 according to whom the epithelium becomes lifted 

 almost bodily from its bed, the space between it and the stroma 

 being filled with blood. Gebhard concludes that the blood 

 eventually reaches the uterine cavity by being forced between 



1 Moricke, " Die Uterusschleimhaut in der verschiedenen Altersperioden 

 und zur Zeit der Menstruation,'-' Zeitsch.f. Geburtshillfe u. Gyndk., vol. vii., 1882. 



2 Findley, "Anatomy of the Menstruating Uterus," Anier. Jour. Obstet., 

 vol. xlv., 1902. 



3 Gebhard, " Ueber das Verhalten der Uterusschleimhaut bei der Men- 

 struation," Verhand cl. Gesells. f. Geb. u. Gyn. zu Berlin, Zeitsch.f. Geb. u. Gyn.> 

 vol. xxxii., 1895. 



