The Development of tlie Hymen 



97 



be at a loss to interpret the various structures were it not that we are 

 able to follow them in series and thus to determine their relationship 

 to their surroundings. Only two layers can be differentiated in this 

 specimen, the middle layer of embryonal connective tissue being absent. 

 The epithelial layer is similar to that in Embryo 4, except that larger 



Fig. 4. Sagittal section a little to right of median line thvougn lower 

 genital tract (Embryo 5). Section No. 179. F., fold; H., hymen; R., ventral 

 wall of rectum ; S., sphincter aui muscle ; U., lu'ethra ; V., vagina. Magnified 

 5 X. 



quantities of desquamated cells are found lying in the vaginal lumen. 

 The connective tissue fibres take the fuchsin stain deeply and are more 

 densely compacted than in Embryo 4. 



We can again distinguish two folds or membranes. The outer fold 

 is lined externally by vulvar epithelium, internally by vaginal epithe- 

 lium (Fig. 8a). Its connective tissue fibres (Pig. 8) are partly con- 

 tinuous with the connective tissue of the vagina. In part they 

 intermingle with the connective tissue of the vulva and perineum. Ee- 

 constructed, this fold has somewhat the shape of a thin crescent, 

 whose concave margin faces the urethra. It springs almost wholly from 

 the dorsal wall. A short projection can be seen opposite on the ventral 



