314 



PROTOZOOLOGY 



inclined to think that sexual reproduction brings about 'zygotic 

 adults.' The nucleus has been studied by Meglitsch (1939). 



E. thomsoni Lucas. In colon of the cockroaches; 7-30// in 

 diameter; very adhesive; 1-3 chromatin blocks on the nuclear 

 membrane; cysts 8-16// in diameter, with 1-4 nuclei. 



E. disparata Kirby. In colon of Microterines hispaniolae; 20- 

 40/i long; active; xylophilous. 



E. majestas K. (Fig. 144, a). In the same habitat; 65-165/t in 

 diameter; many short pseudopodia; cytoplasm filled with food 

 particles. 



E. simulans K. (Fig. 144, h). In the gut of Microiermes pana- 

 maensis; 50-1 50/i in diameter. 



Fig. 144. a, Endamoeha majestus, X420 (Kirby); b, E. simnlans, 

 X420 (Kirby); c, Entamoeba brasiliensis in Zelleriella, X290 (Stabler 

 and Chen). 



E. sahulosa K. In the same habitat; small, 19-35/i in diameter 

 Genus Entamoeba Casagrandi et Barbagallo. Nucleus vesic- 

 ular, with a comparatively small endosome, located in or near 

 the center and with varying number of peripheral chromatin 

 granules attached to the nuclear membrane. It was established 

 by the two Italian authors who were unaware of the existence of 

 the genus Endamoeba (p. 312). Numerous species in vertebrates 

 or invertebrates. 



E. histolytica Schaudinn (Fig. 145, a-f). 20-30/i in diameter; 

 cytoplasm usually differentiated distinctly; eruptive formation of 

 large lobopodia, composed exclusively of ectoplasm; the vesicular 

 nucleus appears in life as a ring, difficult to recognize; food vacu- 



