THE FISH. 83 



the oesophagus enter it? Where does the intestine 

 leave it? 



3. Find the pyloric cseca, at the place where the 

 intestine leaves the stomach. How many? Scrape 

 away the fat and examine one carefully. 



4. Trace the intestine. How many turns does it 

 make? Notice the thin membrane (mesentery) which 

 holds the loops of the intestine together. Where is it 

 attached? Do you find any tubes running in it? 



5. How many lobes has the liver? Where is it 

 attached ? 



6. Find the bile sac, on one of the lobes. Is there 

 a connection between the bile sac and the intestine? 

 Draw. What is the use of the bile sac? 



7. Identify the spleen. This is a small, red body 

 back along the intestine. 



The Reproductive and Excretory Organs. 



1. Identify the reproductive organs, male or 

 female. If a female, the ovaries will show the eggs. 



2. Is there a tube leading from the reproductive 

 organs? Where does it open? 



3. Find the kidneys. They are dark, slender 

 bodies along the roof of the abdominal cavity. 



4. Trace the kidneys backward to the urinary 

 bladder. Where is the outlet? 



The Circulation. 



1. Identify the heart. The larger, angular por- 

 tion is the ventricle. The softer, irregular portion is 

 the auricle. 



2. Find the venous sinus, a dark, thin-walled sac 

 extending back from the auricle and in front of the 

 false diaphragm. Can you find its opening into the 

 auricle? 



3. Find the hepatic vein, passing from the liver 



