1904.] Production of a Specific Gastrotoxic Serum. 143 



corpuscles. The term " specificity " used strictly should not, therefore, 

 be applied to the gastrolytic serum itself, but to that part of it which 

 has a specific affinity for the receptors peculiar to the gastric cells. 



(c) Changes in the Rabbit's Peritoneum. 



If an animal which has received several injections be killed a few 

 weeks after the last one, the peritoneum will show slight opacity and 

 thickening in various places, or slight adhesions between adjacent 

 coils of intestine may be seen, or small pedunculated nodules may 

 be present. The remaining portions of the peritoneum are quite 

 normal. 



The nodules on section are found to be composed of concentric 

 layers of fibrous tissue, generally inclosing within them a group of 

 epithelioid cells, and occasionally a giant cell, the nuclei of which are 

 arranged in the centre. Whether these nodules are formed during 

 the absorption of the stomach cells, as they were not seen in the cases 

 in which an extract of stomach cells was injected, or owing to the 

 presence of isolated bacteria, I am not prepared to state. At any 

 rate, a bacteriological examination of such a peritoneum shows that it 

 is sterile. 



A few days after an injection the peritoneum is in places smeared 

 over with a thin layer of cheesy material, and masses of the same 

 material may exist between the coils of the intestine ; elsewhere the 

 peritoneum is normal. Microscopically, this substance consists of 

 proliferated peritoneal epithelium and exuded leucocytes. This 

 substance is also sterile on cultivation. 



Last year, after I had commenced the present research, a paper was 

 published by Theohari and Babes on a gastrotoxin. This is the only 

 paper, so far as I am aware, dealing with the subject, and, as the 

 authors obtained different results from mine, I will here briefly 

 enumerate them. 



The mucous membrane of the dog's stomach was subcutaneously 

 injected into the goat, and, on injection of the goat's serum into the 

 dog, they obtained the following results : 



(1) Pronounced hypersecretion of the stomach cells in the case of 

 the weak gastrotoxic serum. 



(2) Rapid death, with intense hypersemia of the stomach, and 

 especially of the intestine in the case of the stronger serum. 



(3) In small doses, excitation of gastro-intestinal peristalsis and 

 intestinal haemorrhage. The chief cells in the stomach show functional 

 changes ; the marginal cells show degenerative changes. No change 

 in the pyloric region of the stomach or the large intestine. 



(4) The serum, specific against the peptic region of the dog's 

 stomach, produces, moreover, material alterations in the small 

 intestine, whilst the large intestine remains normal. 



