98 PROTOZOAN PARASITISM 



eiidoplasm is granular, and there is no sharp delinea- 

 tion of ectoplasm. In this small sluggish precystic 

 form it is not safe to attempt differentiation from E. 

 histolytica in unstained specimens, nor probably in 

 stained preparations except in expert hands. 



The cyst is the form to be positively identified by 

 any who can find these bodies and can count the nu- 

 clei in unstained or stained preparations. The 

 cysts usually show in characteristic appearance in 

 formed stools, measuring from ten to thirty or more 

 microns in diameter but usually between fifteen and 

 twenty. They are larger than cysts of E. histolytica 

 as a rule. They are rounded, have a rather thick 

 wall, the body is finely granular or hyaline in the liv- 

 ing cyst and they have typically eight nuclei. Chro- 

 matoid bodies are not conspicuous in the mature cyst. 

 They appear as splinters or slivers or filamentous 

 lines. Sixteen nuclei, or even thirty-two, may be 

 seen. In the immature cysts glycogen is prominent, 

 especially in the iodine preparation, the nuclei are 

 larger and the chromatin more prominent, the chro- 

 matoid bodies are more common and more numerous, 

 and the nuclei are one, two, or four in number. The 

 writer (1924) has observed Endamoeha coll (unless 

 it be Councilniania) which showed constantly a chro- 

 matoid body of round form about the size of the ma- 

 ture nucleus, in the cyst. 



The nucleus hi E. coli is characteristic and may 

 usually be seen in the living organism at any stage. 

 In the very active streamingly motile form it may be 



