16 THE FROG 



6. The Visceral Veins 



Passing from the organs to which you just traced the vis- 

 ceral arteries, trace the visceral veins. 



72. From the rectum and small intestine, numerous 

 small vessels converge in the mesentery proper to 

 form the intestinal vein. 



73. The splenic vein joins one of the large tributaries 

 of the intestinal vein which collects blood from the 

 rectum. 



74. The gastroduodenal vein carries blood from the 

 duodenum and pyloric end of the stomach into the 

 intestinal vein, passing through the gastro-duodenal 

 omentum. 



75. The gastric veins from the right and left sides of 

 the stomach join with the intestinal vein as it courses 

 along the hepato-duodenal omentum, to form 



76. the hepato-portal vein, which enters the liver. It 

 is largely obscured by the pancreas through which 

 it passes at this time. From this gland it receives 

 numerous small pancreatic veins, too small for 

 practical demonstration. 



77. From the point where the hepato-portal vein enters 

 the liver, trace back a small vein, the ramus 

 descendens of the abdominal vein, which you have 

 already identified (27). Note that two other rami 

 are given off from the abdominal vein at this point, 

 which enter the right and left lobes of the liver. 



78. Trace the abdominal vein back along the ventral 

 surface of the body wall until you find its origin, 

 the union of two pelvic veins, one from each leg. 



79. At the point of union of the pelvic veins locate a 

 small vein from the bladder, the vesical vein. 



