AMEBIC DYSENTERY. 689 



account they held the amebse to be the sole cause 

 of the dysentery. 



According to Schaudinn and Craig, ameboe are 

 of two types. One of non-pathogenic character 

 (Entamoeba coli) found b}' Craig in 50 per cent, 

 of normal stools; the other pathogenic (Entamceba 

 Uistolytica) . 



According to Schaudinn, the two organisms dif- 

 fer in morphology and method of reproduction. 

 Walker fails to confirm these observations. 



The principal lesions occur in the large intes- 

 tine, in which are found round or oval ulcers with 

 infiltrated or undermined edges. The ulcers may 

 increase in size, or coalesce with others, and cause 

 the sloughing of large areas of the mucosa or even 

 of the muscular coats. The organisms are found 

 in the intestinal contents, on the surface of the 

 ulcers, in the infiltrated base and edges, and in the 

 underlying tissues. They have been found as- 

 sociated with both chronic and acute appendi- 

 citis. Amebic liver abscesses are not infrequent 

 in those regions in which the disease is endemic. 

 The organisms probably extend to the liver from 

 the intestines through the lymphatic or portal 

 vessels. Not infrequently the association of the 

 amebse with bacteria is missed in the abscesses, 

 and in these instances a "cold" abscess containing 

 much necrotic material and detritus is produced. 

 If contaminated with bacteria the abscesses have 

 a more purulent character. 



Suitable prophylaxis against amebic infection is 

 suggested by the known distribution of these or- 

 ganisms. Of principal importance is the use of fil- 

 tered or boiled waters and the avoidance of un- 



