14() Dr. C. Bolton. On the [July 26, 



brownish coagulated mass in which no structure can be made out; at 

 other times strands of interstitial tissue alone can be seen, the gland 

 cells having completely disappeared. 



A definite ulcer is formed by the gradual disappearance of the 

 necrosed tissue. The blood in the vessels is generally normal, and 

 frequently so when they are situated inside the necrosed patch. In 

 the other cases it is apparently haemolysed, and in one case a large mass 

 of haemolysed blood was seen infiltrating the submucous tissue. 



The remaining portions of the alimentary canal have invariably 

 been found to be normal, and no lesion has been detected in any other 

 organ of the body. The primary lesion in this necrotic process is, 

 I think, undoubtedly the result of a direct action of the gastrotoxin 

 upon the gland cells, with a subsequent digestion of this tissue by 

 the gastric juice, the black colour being due to the action of the 

 gastric juice upon the blood which is contained in the necrosed patch. 



As no change as a result of the action of the gastrotoxin in vitro can 

 be made out, the questions must be raised whether the serum can 

 produce necrosis when it attacks a cell having its normal lymph 

 supply and normal connections in the body, or whether it only 

 produces a devitalisation of the cell, thus allowing of its digestion by 

 the gastric juice, which in this way renders the lesions visible. 

 Previous work upon other cytotoxins does not settle the question one 

 way or the other, because in some cases necrosis has been stated to 

 occur, as in the liver, whilst in other cases no change has been found 

 whatever, as in the pancreas and suprarenal body. 



Haemolysis undoubtedly occurs to a variable extent in different 

 cases, and may account for a part of the haemorrhage, though usually 

 no laking of the blood can be seen in the vessels of the stomach. 



In my opinion the lesions are not primarily due to haemorrhage, 

 because the appearance of a haemorrhagic erosion is different from the 

 necrotic patches described above; there are no haemorrhages to be 

 seen in the mucous membrane of the stomach, such as one would 

 expect, and none occur in any other organ of the body. There is, 

 moreover, no reason to suppose that the capillary endothelium of the 

 stomach is sufficiently special in constitution to evoke the formation 

 of a specific endotheliolysin. 



Infarction can also be excluded by the limitation of the lesion to 

 the mucous membrane, by the very irregular shape of the large patches, 

 which sometimes contain islands of normal tissue, and by the fact 

 that no clots can be found in the vessels either of the stomach or any 

 other organ. 



In some cases where the haemolytic factor is more than usually in 

 evidence, there is no doubt that some of the erosions may be the result 

 of such a factor, but in my experience these erosions present quite a 

 different appearance from the necrotic patches described above, the 



