AMCEB.E OF THE INTESTINAL TRACT. 179 



appears to me to be impossible to conclude otherwise 

 than that Entamceba Mstolytica is the cause of a form 

 of amoebic dysentery. The character of the lesions 

 present in this condition, the constant association of 

 this species with the lesions, and the production of 

 similar lesions in susceptible animals, with infected 

 material, I consider conclusive proof that this para- 

 site causes amoebic dysentery in man. 



Cultivation. The subject of the cultivation of 

 this species of amoeba will be considered in the section 

 dealing with Entamceba tetragena, but I will here 

 state that I have tried all the methods recommended 

 by those who claim to have been successful in cul- 

 tivating these organisms, but have never been able 

 to secure growth upon artificial media. In a recent 

 article Noc appears to have been successful in cul- 

 tivating an amoeba occurring in dysentery in Cochin 

 China, which bears a very close resemblance, as in- 

 dicated in his description, to Entamoeba histolytica, 

 or tetragena, but up to the present time his observa- 

 tions have not been confirmed. 



ENTAM(EBA TETRAGENA. Viereck, 1907. 



In 1907, Viereck described an amoeba occurring 

 in patients suffering from dysentery contracted in 

 Africa which he considered a new species, and to 

 which he gave the name Entamoeba tetragena. Dur- 

 ing the same year an independent description of the 



