456 



PROTOZOOLOGY 

 a b 



Fig. 209. The development of Sphaeromyxa sabrazesi (Debaisieux). 

 a, vegetative nuclei; b, association of two vegetative nuclei; c, the 

 sa-me within a cell; d, primary propagative cell; e, its division; f, sec- 

 ondary propagative cells; g, their division; h, formation of sporocyte; 

 i, two sporocytes; j, formation of pansporoblast; k, pansporoblast at 

 later stage; 1, pansporoblast with two spores, the sporoplasm of which 

 contains two nuclei; m, four nuclei in sporoplasm; n, two nuclei re- 

 main functional, the other two degenerate; o, fusion of the two nuclei. 



cytoplasmic changes prior to, and during, spore-formation, there 

 is a diversity of opinions. To illustrate the views held by those 

 who believe there is a sexual phase in the development of a myxo- 

 sporidian, Sphaeromyxa sabrazesi (p. 465) may be taken as an 



