54 EXPERIMENTAL PHYSIOLOGY 



that are connected with the intestine (pyloric end) and with 

 the esophagus, or gullet (cardiac end). Note the covering 

 of blood vessels. 



In the fold of the intestine (duodenum) next to the stom- 

 ach, locate the fatty-looking pancreas. Find its duct and 

 trace its connection with the duodenum. 



Press forward the liver and, on its posterior surface, find 

 the bile sac. Locate the connection of this with the two 

 lobes of the liver (the hepatic ducts). Open this sac and, 

 with the probe, find its connection (the bile duct) with the 

 pancreatic duct and the duodenum. Note that the bile duct 

 and pancreatic duct fuse and enter the duodenum by a com- 

 mon duct. 



Examine the membrane (mesentery) which supports the 

 intestine. Note its blood vessels. Carefully unravel the in- 

 testine (Caution! do not break it) from the stomach to the 

 anus. Determine the relative lengths of the small and the 

 large intestine and the method of their joining. (This con- 

 nection is guarded by a valve* which acts in such a way as 

 to prevent matter returning from the large to the small 

 intestine.) 



Slit the stomach just below the gullet entrance and, with 

 the probe, find its connection with the mouth. Above 

 the liver and the stomach, find the muscular partition 

 (diaphragm) separating the abdominal from the thoracic 

 cavity. 



Illustrate, by a diagrammatic drawing, the connections 

 of the following parts: mouth, gullet, stomach, liver, pan- 

 creas, small intestine, large intestine. 



Carefully remove the stomach, liver, pancreas, and intes- 

 tines, and preserve the rest of the animal for further dis- 

 section in 85% alcohol or 4% formalin. 



