Chap, i.] TISSUES AND MECHANISMS OF DIGESTION. 353 



frequently found partially digested, viz. in ises when death has 

 taken place suddenly on a full stomach. In an i linary death, 

 membrane a sest i secrete before the circulation is at an end. 

 .: there is no special virtue in living things which prevents 

 ir Wing digested is shewn by the fact, that the leg of a living 

 fr g or the car of a living rabbit introduced into the stomach i 

 dog through a gastric fistula is readily digested. It has 

 suggested that the blood-current keeps up an alkalinity sufficient 

 to neutralize the I ty of the juice in the region of the glands 

 themselves . but this will not explain why the pancreatic juice, 

 which is active in an alkaline medium, does not digest the 

 • 3 of the pancreas itself, or why the digestive cells of the 



bloodless binozoon or hydrozoon do not digest themselves. We 

 might add. it does nor explain why the amoeba, while dissolving 

 the protoplasm of the swallowed diatom, does not dissolve 

 own protoplasm. We cannot answer this question at all at 

 present, any more than the similar one. why the delicate pi - 

 plasm of the amoeba re-ists during life the entrance into it- 

 by osmosis of more water than it requires to carry on its work, 

 while a few moments after it is dead water enters freely by 

 sis, and the effects of that entrance became abundantly 

 evident by the formation of bullae and the breaking up of the 

 protoplasm. 



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