60 ZOOTOMY. 



The true adrenals or supra-renal bodies are small yellow masses in 

 connection with the sympathetic ganglia. 



130. The cardinal veins (Fig. 17, <rrf) lying to the ventral side of 

 the ureters, receiving veins from the l^idneys, uniting with one another 

 posteriorly by a transverse anastomotis, and passing forwards to enter 

 the cardinal sinus (§ 109). 



131. The dorsal aorta (Fig. 20, d.ao), a delicate artery- 

 lying in the middle line between the kidneys, to which it 

 sends branches. (See § 157). 



XXX. Dissect away the tkin from the ventral face of one of the 

 pelvic fins, and make out 



132. The gland of the clasper, consisting cf a large ovoidal sac 

 with thick muscular wallp, which leads by a widish passage at its 

 posterior end into the cavity of the clasper, and which receives the 

 secretion of the gland itself. This is seen by cutting away the ventral 

 wall of the sac to consist of two lobes, with a longitudinal groove 

 between them, in which are the numerous papillifonn terminations of 

 the efferent ducts. 



In the female. 



XXXI. Turn over one of the oviducts and the corre- 

 sponding half of the cloaca to the opposite side of 

 the body, so as to expose one of the kidneys : 

 dissect out — 



133. The ureters (Fig. 19 w), delicate tubes proceeding 

 from the inner edge of the kidney : those coming from the 

 anterior part of the gland pass backwards, those from its 

 posterior part forwards, towards the dorsal wall of the 

 urinary bladder, which they enter. 



134. A delicate thread proceeding forwards from eacK 

 horn of the bilobed bladder, and presenting slight enlarge- 

 ments at intervals : this is the parovarium (Fig. 19, nut.d) 

 the rudiment of the anterior part of the Wolffian body or 

 mesonephros of the embryo, and answering to the parorchis 

 in the male. 



XXXII. Remove the ventral wall of the urinary bladder, and n&te 



