292 



PLASMODROMATA AND SARCODINA 



metamitosis the polar caps of archoplasm situate in the cytoplasm 

 assist in the mitosis. 



2. Gemmation. — In gemmation the nucleus divides usually by- 

 mitosis into two or more nuclei, which either travel to the peri- 

 phery, and become surrounded by small masses of protoplasm, 

 which separate from the parent parasite— ectogenous gemmation — 

 or remain in the cytoplasm, a portion of which becomes differ- 

 entiated around each nucleus— endogenous gemmation. 



The explanation of the two methods is that in ectogenous gemma- 

 tion the buds are separated from the mother cell externally, while 



Fig, 42.— Diagram of the Life-Cycles of Loeschia coli Loesch, emendavit 



SCHAUDINN, 1903, SHOWING HaRTMANN AND WhITMORe'S ViEWS AS TO 



Zygosis. - 



I, Loeschia coli; a-e, stages in the process of binary fission by promitosis; 

 A-D, schizogony by repeated division; 2-12, sexual reproduction or sporogony ; 

 II are the gametes, 12 the zygote, but these stages are not definitely known. 



in endogenous gemmation the localized budding area sinks into the 

 body substance of the mother cell, with the result that the buds are 

 contained in a brood sac. This localized endogenous area is called 

 a pansporoblast, though in some the entire organism forms a pan- 

 sporoblast, which is considered to be phylogenetically derived from 

 the localized condition — i.e., the whole cell represents only the 

 pansporoblast. 



