528 DYSENTERY. 



forms not only by the presence of amoebae but also by its 

 pathological anatomy. The results of these observers have 

 been confirmed by those obtained in Egypt by Kruse and 

 Pasquale, who have also supplied important facts regarding 

 the pathogenic effects of the amoebae when inoculated into 

 animals. The following description is chiefly taken from 

 the monographs of the four writers last mentioned. 



Amoebic Dysentery Characters of the Amoeba. The 

 amoebae, as seen in the stools of a case of dysentery, are 

 rounded or somewhat irregular protoplasmic masses, usually 



1C: 



m 



F) 



FIG. 125. Amoebae of dysentery. 



a and b, amoebae as seen in the fresh stools, showing blunt amoeboid processes of 

 ectoplasm. The endoplasm of a shows a nucleus, three red corpuscles and numerous 

 vacuoles ; that of b, numerous red corpuscles and a few vacuoles. 



c, an amoeba as seen in a fixed film preparation, showing a small rounded nucleus 

 (Kruse and Pasquale). X 600. 



measuring about 25 to 35 /z in diameter, though both 

 larger and smaller forms are met with. 



When the parasite is at rest it has a more or less 

 rounded shape ; the protoplasm is finely granular and of 

 refractile appearance, and is without differentiation into 

 layers. The organism may show sluggish amoebic move- 

 ments at the ordinary temperature, but these become much 

 more active when a warm stage is used. When they 

 occur, the amoeba shows differentiation into a central 

 granular endoplasm and an outer hyaline layer or ectoplasm 



