66 



EXPERIMENTAL PHYSIOLOGY 



XLI. MICROSCOPIC ANATOMY OF THE DIGESTIVE TRACT 



(OPTIONAL). 



Apparatus. Prepared slides of the cross sections of the walls 

 of the esophagus (middle part), stomach (pyloric section), small 

 intestine (injected blood vessels); compound microscope. 



Directions. Make drawings of each section studied and 

 label the parts. See Figs. 30 and 31. 



FIG. 30. Vertical Section 

 of the Coats of the 

 Stomach: d, surface of 

 mucous membrane, and 

 mouths of gastric folli- 

 cles; ra, gastric tubuli, 

 or follicles; mm, dense 

 connective tissue; sra, 

 sub-mucous tissue; cm, 

 transverse muscular fi- 

 bers; Im, longitudinal 

 muscular fibers; s, fi- 

 brous, or serous, coat. 



FIG. 31. Section of Injected Small Intestine 

 of Cat: a, 6, mucosa; g, villi; i, their absorb- 

 ent vessels; h, simple follicles; c, muscularis 

 mucosse; d, sub-mucosa; e, e', circular and 

 longitudinal layers of muscle; /, fibrous coat. 

 All the dark lines represent blood vessels 

 filled with an injection mass. 



