THE NECTURUS 53 



Note where its duct enters the lower part of the 

 duodenum. 



Spleen 



The spleen is a dark body, that is attached to the 

 stomach by the gastrosplenic membrane. Show this in the 

 drawing of the digestive system. The spleen is not a part 

 of the digestive system. 



Lungs 



Posterior to the stomach, note the two lungs. They are 

 small and are usually collapsed and empty of air. Insert 

 a small blow pipe and inflate them to see their size. Note 

 the length of the lungs and chart their position in the 

 pleuro-peritoneal cavity. Follow the lungs forward and 

 find the glottis. 



If the specimen is a female, the oviducts may be seen 

 extending forward under the other organs along the back 

 wall. 



Split the digestive tract from the anterior end of the 

 stomach to the intestines. Note the ducts that enter the 

 system and the different character of the lining in the 

 different parts. 



Membranes 



There are several membranes. Their position is given 

 in the table below. 



Mesohepar, from the liver to the ventral wall of the body 

 Gastrohepatic, from the liver to the stomach 

 Mesogaster, from the stomach to the dorsal wall 

 Gastrosplenic, from the stomach to the spleen 

 Hepato-duodenal-omentum, from the liver to the intestine 

 Mesorectum, posterior part of the intestine to the body wall 



Drawing 18. Use one of the specimens to make a drawing of the 

 entire digestive system to show the relative length and position of the 

 different parts. 



