AMGEBJE OF THE INTESTINAL TRACT. 147 



The invasion of the mucous membrane laterally 

 leads to the formation of sinuses beneath this mem- 

 brane, connecting the neighboring ulcers. This lesion 

 is one most characteristic of amoebic dysentery and 

 does not occur in any other form. Upon opening 

 such sinuses it is generally found that they contain 

 gelatinous material similar to that contained within 

 the nodules and microscopic examination reveals the 

 presence of numerous amoeba?. 



In aggravated cases the necrosis of the mucous 

 and submucous coat of the intestine as well as the 

 coalescence of smaller ulcers, leads to the formation of 

 irregular ulcers of large extent, the mucous mem- 

 brane between them presenting deep, irregular chan- 

 nels produced by the necrosis of the tissue covering 

 the sinuses, while the whole surface of the intestine is 

 covered with partly detached shreds of necrotic mem- 

 brane. This so-called " buffalo skin " appearance is 

 very frequently present in severe cases of amoebic 

 dysentery and is very characteristic of that disease. 



It is very difficult to describe the various forms 

 of ulceration which may be present in the intestine 

 in amoebic infection. A typical ulcer may be said to 

 have the following structure: the edges are consider- 

 ably raised from the surface of the mucous membrane 

 and are much undermined, presenting a very charac- 

 teristic shaggy appearance due to necrotic tissue ; the 



