FORMATION OF HYDROCHLORIC ACID IN THE FOVEOL^. 235 



citrate in equal quantities were injected subcutaneously. On the 

 fourth day the cat died, but the tissues were immediately fixed 

 in neutral formalin. There was more Prussian blue in the 

 immediate neighborhood of the sutures than in other parts of 

 the mucous membrane. 



These results answer the second question in the affirmative. 

 And they show that dead parietal cells show more Prussian 

 blue than living ones. The dead ones are always stained by it, 

 whereas most of the living ones are not. This suggests that the 

 death of the parietal cell or a lowering of its vitality may permit 

 or facilitate the penetration of the cell by substances concerned 

 in the Prussian blue reaction, and that dead cells become acid. 



Effect of Poisons on Amount of Prussian Blue Precipitate 

 Third, is the extent of the Prussian blue reaction increased by the 

 injection of poisons into the \vall of the stomach? We injected 

 into the submucous tissue of the stomach exposed under aseptic 

 precautions, solutions of phosphorus in olive oil, and solutions of 

 moccasin venom in distilled water. The incisions in the ab- 

 dominal wall were closed and salts of sodium ferrocyanide and 

 iron and ammonium citrate injected subcutaneously for varying 

 periods. The results were negative; we could not demonstrate 

 any increase of the Prussian blue reaction in the area where these 

 poisons were injected. 



Effect of Restriction of Blood Supply on Amount of Prussian 

 Blue Precipitate. Fourth, is the amount of Prussian blue in- 

 creased in areas of restricted blood supply? 



Arteries and veins of various sizes were tied on the stomachs 

 of different rabbits and cats. Solutions of sodium ferrocyanide 

 and iron and ammonium citrate were injected subcutaneously 

 during several days. The results answered this question in the 

 negative. There was no increase of Prussian blue in the areas of 

 restricted blood supply. In a few cases ulcers were produced and 

 on the surface of these there was always a considerable deposit 

 of Prussian blue. The cells on the surface of the ulcer belonging 

 to various parts of the gastric glands and presumably dead or 

 dying always showed a considerable deposit of Prussian blue 

 in them. 



Precipitates Do Not Back into Gland Lumina from the Surface. 



