INTESTINAL SYSTEM 219 



Man . . . . .16-17 gm. 



Dog . 20 



Cat . 15 



Sheep ... 25 



Rabbit .... 137 ,, 



Porpoise ..... 175 ,, 

 The proportions of glycocholic and taurocholic acids vary 

 greatly in different species ; taurocholic acid is found either 

 alone or in great excess in the bile of all carnivora, of the herbi- 

 vorous sheep and goats, of birds, snakes and fishes ; glycocholic 

 acid predominates in oxen, hares, rabbits, kangaroos, pigs and 

 men. 1 



In addition to the well-known action of bile in emulsifying 

 fats, it possesses another very important property, namely, that 

 of rendering inert and excreting alkaloidal and metallic poisons 

 passing through the liver, just as the liver itself converts the 

 poisonous ammonia salts in the portal blood to the non-poisonous 

 urea ; such are some of the powerful protective arrangements 

 with which the body is provided. 2 



No less important than the liver is the part taken by the 

 pancreas in the digestive processes of man and animals. In 

 herbivora, whose digestion is never entirely at rest, the secretion 

 of the pancreas is constant ; in carnivora and omnivora the 

 pancreatic secretion only continues during the temporary periods 

 of digestive activity. The daily output is difficult to determine ; ! 

 Bidder and Schmidt give the following figures : 3 

 In man up to 1 50 gm. per diem 

 horse 180 ,, hour 



ox 200-270 



pig 12-15 ,, 



The secretion flows from the pancreas to the small intestine 

 by the pancreatic duct, a second accessory duct existing in 

 man, carnivora and horses ; furthermore, it has lately been 

 demonstrated that the gland gives rise to a peculiar internal 

 secretion which controls the carbohydrate metabolism in man 

 and mammals. Animals after extirpation of the pancreas 



1 Munk-Schultz, loc. fit., p. 164. 

 'Ibid., pp. 229-32. 

 3 1 bid., p. 175. 



