PISCES 



189 



segment ally arranged to begin with, but the ridge they form 

 on each side, the genital ridge of the peritoneum, suffers a 

 reduction and concentration. 



This introduction will serve to make plain the condition 

 of the adult organs. 



The spermatozoa are liberated into tubes in the testes of 

 the male, and these tubes open into the anterior tubes of the 

 mesonephros and are the vasa efferentia, which fuse to form a 



Remnant of 



MiiUerian duct 



Vas. effer. 



Test 



Wolffian duct 



Ureter. 

 Sem. ves. 

 Sperm sac 



Urinogen. pap. 

 Abdom. pore. 



nt. opening 

 Mullerian duct 



Ovary 



Oviducal gld. 

 Wolffian duct 



Oviduct dis- 

 tended by egg 

 Ureter 



Urin. papilla 

 Ext. opening 

 Mullerian duct 



Abdom. pore 



FIG. 96. Raia. Male (left) and female (right) reproductive organs of adult. 



marginal duct leading into the mesonephric duct or Wolffian 

 duct. The duct is highly convoluted and forms a compact 

 organ extending almost the length of the peritoneal cavity. 

 This organ is called the epididymis, or Wolffian body. The 

 two vasa deferentia as they emerge from the epididymis 

 become dilated to form seminal vesicles and give off blind 

 sperm sacs. They join to form a urinogenital sinus with the 

 ureters from the kidney or functional part of the mesonephros. 

 The sinus opens by a papilla which projects into the cloaca 

 from the dorsal wall. The kidneys are large, red in colour, 

 and lie one on each side of the vertebral column at the hinder 

 end of the peritoneal cavity. 



In the female the large ova, which are light yellow in colour, 



