352 



PROTOZOOLOGY 



membrane thick; in life, filled with numerous granules of uniform di- 

 mensions along its peripheral region; upon fixation, a fine chro- 

 matic network becomes noticeable in their stead; central portion 

 coarsely reticulated; with several endosomes between the two zones 

 (Fig. 164, a); in some, cytoplasm becomes prominently striated dur- 

 ing locomotion; in the intestine of invertebrates. 



Fig. 165. Endamoeba blattae. a-c, trophozoites in fife, X530; d, a stained 

 binucleate amoeba; e, f, stained and fresh cysts, X700 (Kudo). 



E. hlattae (Biitschli) (Figs. 51; 165). In the colon of cockroaches; 

 10-150/x in diameter; rounded individuals with broad pseudopodia, 

 show a distinct differentiation of cytoplasm; elongated forms with 

 a few pseudopodia, show ectoplasm only at the extremities of the 

 pseudopods; endoplasm of actively motile trophozoites shows a 

 distinct striation, a condition not seen in other amoebae; fluid-filled 

 vacuoles occur in large numbers; amoebae feed on starch grains, 

 yeast cells, bacteria and protozoans, all of which coexist in the host 

 organ; cysts, 20-50/x in diameter, commonly seen in the colon con- 

 tents, with often more than 60 nuclei. The life-cycle cf this amoeba 



