The Digestive System. 49 



being secreted three to four hours after a raeal, food exer- 

 cising an influence on the quantity. Pats are acted upon 

 by the bile, being split up into fatty acids and glycerine, 

 emulsified and then saponified, in which state they are 

 capable of being absorbed. Bile has a mildly purgative 

 action; its suppression is revealed by constipation, stink- 

 ing feces and yellowness of the mucous membranes. A 

 secreting gland of even more importance than the liver is 

 the pancreas; the reason of such importance is owing to 

 the fact that its secretion, the pancreatic juice, contains 

 ferments which are more powerful than those secretions 

 (the saliva, gastric juice and bile) heretofore discussed, 

 yet such being the case there is a relation between bile 

 and pancreatic juice. Bile being alkaline neutralizes the 

 acid (it will be remembered that the stomach contents 

 were acid) and thus assists the pancreatic secretion, 

 which in its turn liberates the fatty acids before men- 

 tioned. The organ secreting the abdominal saliva, as the 

 pancreatic juice has been called, is known as the pan- 

 creas; it is of a reddish cream color, and is situated 

 behind the stomach and liver and in front of the kid- 

 neys. Its duct (Wirsung's) joins that of the liver in 

 the horse, not in cattle and sheep. Pancreatic juice is 

 a colorless alkaline fluid of a varying composition, de- 

 pending on the state of secretion. This juice contains 

 a large amount of solids and is readily decomposed, the 

 process being evidenced by the fecal odor. It contains 

 four ferments, one that acts on starch (amylolytic), one 

 that acts on proteids (proteolytic), a fat splitter (into 

 fatty acids and glycerine) and a milk curdling ferment, 

 similar in action to rennet. The first ferment converts 

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