HOW TlIK ANIMAL LIVES 221 



bowols, nnd transforms their fatty contents into an 

 ♦'iiiulsioM which penetrates an animal memhrane, 

 aiitl is al)Sorbecl witli great rapidity. 



.')I>7. Bile has, besides, a limited power .of 

 changing starch into sugar. It is also nsrful in 

 currying waste matters out of the body. 



398. Pancreatic juice is poured into the in- 

 testines by a canal which in certain animals unites 

 with the bile duct. It contains at least four 

 dilTereiit ferments : (a) Amylopsiti, which, at 

 the body temperature, rapidly transforms starch 

 and even gum into sugar, thus completing any 

 imperfect work of the saliva ; (h) trypsin, 

 which, ill an alkaline liquid, changes nitroge- 

 nous matters into jieptones, thus finishing any 

 imj)crt"ect work of the stomach ; (r) a milk-cur- 

 dling ferment. 



31>1). The pancreatic juice, as a whole, acts 

 like the bile in causing fats to form emulsions. 

 It even breaks up the fats into fatty acids nnd 

 glycerin. 



40(1. Intestinal juice is a complex niixtuir <'i 

 the ditTereut secretions already name<l, together 

 with the products of the glands of the intestinal 

 walls. The secretions of tlieso walls ai-t like 

 pancreatic juice, only less powerfully. 



401. As a whole, the <ligestivo agents tlirown 

 into the intestines cover the whole field of di- 

 gestion, nnd largely make up for niiy defective 



