IX PRACTICAL DIRECTIONS 459 



the body, just beneath the peritoneum. Cut through the body- wall on 

 one side, a short distance behind the pectoral fin ; insert a cannula, 

 directed forwards, into the cut end of the lateral vein, and inject. The 

 vein will then be seen running forwards as far as the pectoral arch, 

 when it turns towards the dorsal side. 



6. In the female, the united anterior ends of the oviducts and their 

 coelomic aperture, ventral to the gullet ai d just in front of the liver. 



IV. — Taking care not to injure the anterior ends of the oviducts and 

 to leave part of the hepatic sinus in situ, remove the liver, together 

 with the stomach and intestine, without injuring the bile-duct, cutting 

 through the stomach at its junction with the gullet and the intestine 

 iust in front of the rectal gland. Wash out the portion of the enteric 

 canal thus removed under the tap, fill it with water, and place the 

 whole under water in a dissecting-dish. Cut away portions of the wall 

 of both stomach and intestine, and make out — 



1. The course of the bile ducts and pancreatic ducts, and their apertures 

 into the intestine. 



2. The pyloric valve, and the spiral valve of the intestine, which 

 makes about seven or eight close turns, appearing like a series of cones 

 one within the other. 



3. The characters of the mucous viemhrane of the stomach and 

 intestine. 



Sketch your dissection. 



D- ITrinogenital organs. 



I. — After noting again the gonads, and in the male the delicate 

 efferent ducts of the spermaries (Fig. J 18, A), remove in the male all but 

 tlie anterior ends of the latter, and in the female the entire ovary ; then 

 carefully dissect away the thick peritoneum covering the kidneys, noting 

 as you do so the dorsal aorta and its various branches, and once again 

 the cardinal veins (C, § III, 4), which may beinflated with air. The 

 renal portal veins are not easily traced without injection, which may be 

 done from the cut end of the caudal vein. 



Note-^ 



1. The brownish kidneys, and in the male their anterior, whitish 

 sexual part — the epididymes. 



2. In the male : a, the convoluted spermiduct, indistinguishable from 

 the epididymis anteriorly and enlarging posteriorly to form the elongated 

 seminal vesicle ; and b; the grooved, eversible claspers, which are 



