222 



THE UROGENITAL SYSTEM 



Ligaments of the Internal Genitalia. Female. The loose mesen- 

 chyma of the genital cord gives rise laterally to the broad ligaments of the 

 uterus in females. A portion of the primitive genital fold unites the caudal 

 end of the ovary to the genital cord. This acquires connective tissue and 

 smooth muscle fibers and forms the proper ligament of the ovary (Fig. 233). 

 Since the uterus develops in the genital cord, the ligament of the ovary 

 extends to the posterior surface of the uterine wall. In the male the homo- 

 logue of the proper ligament of the ovary is the ligament of the testis. 



In both sexes the inguinal fold extends from the urogenital fold to the 

 inguinal crest, located on the inside of the ventral abdominal wall, a 

 point which marks the future entrance of the inguinal canal. The in- 



Diaphragmatic liga- 

 ment of mesonephros 



Metancphros 

 Ureter 



Inguinal fold 



Clans of phallus 



Suprarenal gland 



MiiUerian duct 

 in mesonephric fold 



Genital gland 



Rectum 

 Genital cord 



Genital swelling 



FIG. 232. Ventral dissection of a human embryo of 23 mm., showing the urogenital organs. 

 The right suprarenal gland has been removed to show the metanephros. 



guinal fold thus forms a bridge in 14 mm. embryos between the urogenital 

 fold, in the middle portion of which the uterus develops in the female, and 

 the abdominal wall at the entrance of the inguinal canal (Fig. 232). In 

 the inguinal crest is differentiated the conical anlage of the chorda guber- 

 naculi, which later becomes a fibrous cord. The abdominal muscles de- 

 velop around it, forming a tube, the inguinal canal, and the external 

 oblique muscle leaves a foramen, through which the chorda connects 

 with a second cord termed in the male the ligamentum scroti, in the female 

 the ligamentum labiale. The chorda gubernaculi and the ligamentum 

 labiale together constitute the round ligament of the uterus (Fig. 233), 

 as they form a continuous cord extending from the urogenital fold to the 

 base of the genital tubercle. With the development of the uterus in the 

 urogenital fold, the round ligament becomes attached to its ventral 

 surface. 



