THE NECTURU3 41 



POSTCAVA 



The large vessel, returning blood from the kidneys and 

 liver, is the first to be studied. Place the animal on its back, 

 turn the liver to the animal's left and gently separate the 

 organs on the midline of the back, so as to see the large 

 vessels between the kidneys. This vessel is formed by 

 numerous venas reheventes coming from the kidneys and 

 from the sex organs. The vein enlarges as it reaches the 

 anterior end of the kidneys bending ventrally to reach the 

 dorsal surface of the liver. Follow it to the hepatic sinus 

 by picking away part of the liver substance. At the pos- 

 terior end, near the entrance into the liver, the postcava 

 receives a vessel the hepatic, from the posterior end of the 

 liver. At the anterior end of the liver, it receives another 

 branch from the anterior lobe of the liver. These veins 

 come from the liver. The hepatic sinuses enter the sinus 

 venosus and right atrium. 



Hepatic Portal 



This system brings the blood to the liver, from the fol- 

 lowing veins, abdominal, splenic, gastric, and mesenteric. 

 Move the liver to the right side of the animal and note the 

 gastric vessels coming into it. There are usually two 

 entering it from the anterior end of the stomach, about a 

 centimeter apart. In the region of the pancreas the veins 

 enter from the spleen, stomach, pancreas, and intestines. 

 Locate the spleen and follow the splenic vein through to 

 the hepatic portal. Small veins coming from the pancreas 

 are added. The mesenteric comes from the intestines. 



Abdominal 



The abdominal is found in the ventral wall of the body. 

 It receives blood from the pelvic veins and the anal region. 



