x PRACTICAL DIRECTIONS 475 



4. The large hepatic sinus, immediately in front of the liver, below 

 the gullet : slit it open, and note the veins entering it from the liver. 

 On either side of the gullet in this region, along the dorsal surface of 

 the coelome, a capacious cardinal sinus will be seen : make an aperture 

 in this, and pass a seeker backwards, noting that the sinus narrows into 

 the cardinal vein, which passes along the inner side of the correspond- 

 ing kidney and parallel to the aorta (Figs. 119 and 122). The genital 

 (spermatic or ovarian] sinus communicates with the cardinal. 



5. The lateral veins, running on either side of the body just beneath 

 the peritoneum. Cut through the body-wall on one side, a short dis- 

 tance behind the pectoral fin ; insert a cannula, directed forwards, into 

 the cut end of the lateral vein (see Fig. ill), 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 and 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 

 just 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 membrane of the stomach and 

 intestine. 



Sketch your dissection. 



D. Urinogenital organs. 



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

 efferent ducts of the spermaries (Fig. 127, A), remove in the male all but 

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

 carefully dissect away the thick peritoneum covering the kidneys, noting 





