THE ESSENTIAL PHENOMENA OF DIGESTION. 



41 



in some respects analogous 

 to that of yeast, and which 

 is called pepsin. 



The gastric juice acts on 

 nitrogenous matters, such 

 as meat, white of egg, 

 cheese, the gluten of bread, 

 etc. It dissolves them and 

 renders them absorbable. 



It has been stated, in the 

 description of the small in- 

 testine, that the ducts car- 

 rying the bile and the pan- 

 creatic juice open only a 

 short distance from the 

 pylorus. 



The pancreatic juice, an 

 alkaline liquid, whose ap- 

 pearance resembles that of 

 the saliva, but which differs 

 somewhat from the latter 

 in composition, acts on the 

 starchy or saccharine mat- 

 ters that have escaped the 

 action of the saliva in pre- 

 cisely the same manner as 



VIEW OF THE GREAT LYMPHATIC 



TRUNKS. 1, 2, thoracic duct ; 4, the 

 right lymphatic duct ; 5, lymphatics 

 of the thigh ; 6, iliac lymphatics ; 

 7, lumbar lymphatics ; 8, intercos- 

 tal lymphatics ; a, superior cava ; b, 

 left innominate vein; c, right in- 

 nominate vein; e, inferior cava; 

 3, left subclavian vein. 



