CHAPTER IV 



The Amoebae (Continued) 



Endamoeba histolytica. Prevalence, Distribution and 

 Transmission. Experimental Information. Cultivation. 

 Habitat and Effects. Chronic Intestinal Amoebiasis. 

 Acute Amoebic Colitis (Amoebic Dysentery). The Stools 

 of Dysentery. Treatment. 



ENDAMOEBA HISTOLYTICA. 



This true parasite, of known pathogenic activity, 

 is the most important of the protozoa of the alimen- 

 tary tract. Discovered by Losch (1875), it has been 

 extensively studied by numerous observers and our 

 information about it is probably more definite than 

 with any of the other alimentary tract protozoa. 



In active stage it is usually of rather characteristic 

 appearance. Rounded up it measures 20 to 30 mi- 

 crons in diameter. When motile it travels rather 

 actively and steadily, the ectoplasm in pseudopodia, 

 at the forefront, the endoplasm with food bodies, if 

 present, following, the flow of the whole organism 

 being somewhat like that of a drop of liquid on an 

 incline to which it adheres somewhat. The ecto- 

 plasm is comparatively clear, in pseudopodia when 



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