-S72 1*R D. BERKY HART. 



Fig. 18. Sagittal mesial section of human embryo, 25 mm., to show 

 ectodermic cloaca, c.l. (Tourneux). 



Fig. 19. Development of permanent anus by inward passage of 

 epidermis, and central desquamation at about third month, a, anus ; 

 ■/", rectum. 



Fig. 20. Sagittal mesial section of three and a half months embryo 

 to show formation of prepuce of the chtoris and development of hymen. 

 S U G, urinogenital sinus (part to form vestibule); W.B., AYolffian 

 bulb; UR, urethra; ep., epidermic plug to form prepuce {-). 



Fig. 21. Wolffian bulbs ; note Wolffian duct ending in smaller one. 

 W.D., Wolffian duct (^^'). 



Fig. 22. Coronal section of pelvis of four and a half months foetus in 

 line of pubic arch, to show hymen. Note two lateral parts of hymen, 

 one from each Wolffian bulb. H, hymen ; B.^., Bartholinian gland. 



Fig. 23. Outline of formation of vagina, showing upper two-thirds 

 originating from the ducts of Midler, the lower third from urinogenital 

 sinus and Wolffian bulbs, ex., cervical canal ; A, Mullerian part ; B, 

 part derived from Wolffian bulbs and urinogenital sinus. 



Figs. 24 and 25 show sagittal mesial section of penis of three and a 

 half months foetus. Fig. 25 shows epidermis {a) passing in behind 

 fraenum under a higher power. 



Fig. 26. Section of glans penis, showing formation of prepuce and 

 tunnelling of glans, near full time, p, prepuce ; ur, urethra. 



Fig. 27. Genital tract of Rat Kangaroo. K, kidney; U, ureter;, 

 C, cornu; I.e., lateral canal; m, central part. 



Fig. 28. Genital tract of Macropus Benneti (Brass). 



Fig. 29. Genital tract of Wombat (Brass). 



Fi". 30. Uterus of Rat Kangaroo to show mucous membrane (?«), 



Fie. 31. Genital cord of Rat Kangaroo. I.e., lateral canal; m,. 

 central vagina; u.r., urethra. 



Fig. 32. Sagittal lateral section of four weeks human embryo (10 

 mm.) to show Wolffian body. Note apparent pronephric tubule {a) 

 at top of Wolffian body. Tubules, glomeruli, and duct of meso- 

 nephros are seen. W.U, Wolffian duct. 



Fi«-. 33. I'ronephric tubule of above. 



Fic'. 34. Nagel's diagram of urinogenital organs in human embryo,. 

 modified hy p)rolongati(m of hmer ends of Wolffian duets. m.d., 

 Midler's duct ; w.d., Wolffian duct ; /r, Wolffian body ; s.<j., Sexual 

 gland ; w.h.. Wolffian bulbs. 



Fig. 35. Ovary and tube of Rat Kangaroo, with Wollhan duct (W) 

 in centre of ovary. 



