THE UEINO-GENITAL SYSTEM, THE 

 ADEENALS, ETC. 



THE URINO-GENITAL SYSTEM. 



By cutting- through the meso-rectum the posterior caval vein is 

 seen, as a large vessel, arising by numerous transverse branches from 

 the ventral surfaces of the kidneys 

 and testes (Fig. 214 Cv), lying in 

 the median line between the kid- 

 neys ; by drawing it to one side the 

 dorsal aorta is brought into view 

 (Fig. 214 Ao). The testes are placed 

 on the ventral surface of the kidneys, 

 and together with the fat-bodies 

 conceal the anterior portions of these 

 organs. The posterior portions of 

 the kidneys are covered by perito- 

 neum only, and may by seen with- 

 out further dissection. The kidneys 

 lie dorsal to the peritoneum, and have 

 this membrane on their ventral 

 surfaces only ; their dorsal surfaces 

 are in contact with the lumbo- 

 sacral plexus. 



The lu-eters extend from the 

 anterior border of the eighth verte- 

 bra to the middle of the urostyle, 

 where they terminate by two orifices 

 in the dorsal wall of the cloaca 

 (Fig. 184). 



The testes are entirely surrounded 

 by i^eritoneum, except a small part 

 {UUus) of the inner surface, where 

 the vessels and ducts enter. 



The urino-genital organs are arranged in the same manner in 

 the two sexes; the ovaries corresponding in position with the 



The male urino-genital organs. 

 An Aorta. 

 t'l Cloaca. 

 Cv Inferior vena cava. 

 FK Fat-body. 

 // Testis. 

 *V Kidney. 

 .S. 61 Openings of ureters. 

 Ur Ureter. 

 Vr Renal veins. 



t Appearance of ureters on the ven- 

 tral surfaces of kidneys. 



