AMOEBAE OF THE INTESTINAL TRACT. 113 



possible to believe that marked lesions of this disease 

 can occur in an intestine without leading to the pro- 

 duction of clinical symptoms. It is possible that in 

 isolated instances a few ulcers might exist in limited 

 regions of the intestine without producing symptoms 

 which would attract the attention of the patient, but 

 that any generalized ulceration can occur without 

 symptoms I am not ready to believe. The lack of a 

 history of diarrhoea or dysentery cannot be depended 

 upon in native races, for such symptoms are not con- 

 sidered of enough importance by these people to be 

 noted. Almost all of Musgrave's cases were in Fili- 

 pinos who suffer continually from diarrhoea and who 

 would not be apt to notice a symptom which is more 

 or less constantly present. We have no record of 

 such, cases occurring in temperate regions among 

 people in whom the symptoms would be apt to attract 

 attention. 



However, the occurrence of the lesions of amoebic 

 dysentery in patients who have not suffered from 

 symptoms of that disease is of no value as an argu- 

 ment against the specificity of Entamceba coli, and 

 I believe there is sufficient evidence at hand to prove 

 conclusively that this species is valid and that it occurs 

 commonly as a harmless commensal in the human in- 

 testine. 



