ORGANS AND PROCESSES OF DIGESTION 



XXXIII. DISSECTION OF A RAT'S DIGESTIVE ORGANS. 



Apparatus. Chloroformed rat, 1 dissecting tray with wax lining, 

 scissors, forceps, bristle probes, 10% alcohol or 1% formalin. 



Directions. Lay the rat on its back in the tray, stretch, 

 and tie or pin the legs as in the diagram. Cover with 10% 

 alcohol or 1% formalin. 



Locate the lower end of 

 the breast bone and slit the 

 skin from this point to the 

 anus. On each side at the 

 middle point of the slit, 

 make a slit at right angles. 

 Turn back the four flaps 

 and pin them. 



Note the thin membrane 

 (peritoneum) lining the abdo- 

 men. Is it flexible? Remove 

 this and, without disturbing 

 the underlying parts, locate 



the stomach, the liver, and 



., T . . . FIG. 27. 



the coiled intestine. 



Press the intestine downward and determine the size, 

 position, shape, and color of the stomach. Find the ends 



1 This exercise may be made a demonstration, 

 animal such as the rabbit would be preferable. 



53 



In that case a larger 



