442 



COMPARATIVE ANATOMY 



persist as functionless rudiments. The former is the appendix testis 

 and the latter the uterus masculinus. 



Remnants of the mesonephros also persist in the female. Some 

 anterior mesonephric tubules unite with the rete ovarii to form the 

 epoophoron. The posterior part of the mesonephros becomes the rudi- 



ly 



pronephric 



ef -" tubule 



[:■ .^y~^"| mesonephric 

 ■ C^^, >— tubules with 



nephrosto 



allantois 



phric duct 

 phric duct 



Fig. 369. — Schematic diagrams to show the relations of pronephros, mesonephros, 

 and metanephros at various stages of development. In the adult male the mesonephric 

 ("Wolffian) duct is retained as the ductus deferens. (From Patten's " Embryology of the 

 Chick.") 



mentary paroophoron. The functionless remnant of the Wolffian duct 

 in the adult is known as Gartner's duct. 



Female Reproductive Ducts. Mueller's ducts parallel the meso- 

 nephric ducts and open into the urogenital sinus median to them. The 

 position of the primary opening marks the place where later the hymen is 

 located. During the fourth month, the posterior portions of the paired 

 Muellerian ducts unite to form uterus and vagina. The anterior portions 

 form the uterine tubes. 



