LOESCHIA 



clearly visible unless coloured by some preparation. When resting it is oval 

 or spherical, but during movement it alters its appearance repeatedly, throwing 

 out pseudopodia and creeping about. The nucleus is small, about 5 jn in 

 diameter, and is poor in chromatin, and placed excentrically sometimes close 

 to the periphery. The limiting membrane is difficult to define, and the 

 amount of chromatin is relatively very small. A small karyosome can some- 

 times be seen in the centre of the nucleus. 



Life-History. — It reproduces in tliree ways: (i) binary fission; (2) gem- 

 mation; and (3) sporogony. 



Fig. 51.— Diagram of the Life-Cycles of Loeschia histolytica 



ACCORDING TO ScHAUDINN'S ViEWS. 



{Constructed from Craig's drawings in the Journal of Infectious Diseases.) 

 A, B, Binary fission; 1-8, spore-formation. 



1. Binary Fission. — This method was only discovered by Schaudinn on 

 examining fresh specimens of the infected alimentary canal. 



The nucleus divides by amitosis into two, and then the cytoplasm splits 

 into two equal daughter cells. 



2. Gemmation. — Gemmation, found more commonly than binary fission 

 by Schaudinn, consists of the division of the nucleus by amitosis into two or 

 more daughter nuclei, which, together with small portions of the cytoplasm, 

 separate off from the mother cell, the daughter cell being smaller than the 

 mother cell. 



3. Spore-Formation. — In spore-formation, which only takes place under 

 favourable circumstances, such as when recovery is taking place after an 



