AMCEB^E OF THE INTESTINAL TRACT. 127 



number of red cells which may be contained within an 

 amoeba is sometimes enormous, and I have often ob- 

 served organisms so filled with these cells that very 

 little of the structure could be distinguished. 



In cases of amoebic dysentery in which both Enta- 

 mceba coli and Entamceba Mstolytica are present 

 it is but seldom that the former contain red blood 

 corpuscles while the majority of the latter may be 

 filled with them. As a rule only two to six red cells 

 are contained within an amoeba, and if the process of 

 digestion is to be studied an organism should be 

 selected which contains from one to two red cor- 

 puscles. If such organisms are kept at body tem- 

 perature the red cells will be seen to gradually break 

 up, the haemoglobin being liberated, imparting to the 

 endoplasm a greenish color. Extrusion of the red 

 cell is sometimes observed, but this is an abnormal 

 process due to unfavorable environment, except in 

 those organisms in which reproductive changes are 

 occurring. 



In many amoebae the red corpuscles become de- 

 colorized, only a delicate shadow of the cell remain- 

 ing visible. Such decolorized corpuscles are often 

 mistaken for small vacuoles, but careful focussing will 

 reveal their nature. These shadow-corpuscles must 

 also be differentiated from the refractile oval bodies 

 to be mentioned. 



