COCCIDIA 



465 



nuclei {k-m). Each of the four nuclei becomes the center of a spo- 

 roblast which secretes a membrane and transforms itself into a 

 spore (r?). Its nucleus, in the meantime, undergoes a division, and 





Fig. 215. The life-cycle of Eimeria schubergi, X400 (Schaudinn). 

 a, entrance of a sporozoite in the gut epithelial cell of host and growth 

 of schizont; b, schizogony; c, macro- and micro-gametocyte; d, e, for- 

 mation of macrogamete; f-h, formation of microgametes; i, mature 

 gametes prior to fusion, j, k, fertilization; 1-n, spore-formation; o, oocyst 

 containing four mature spores, each with two sporozoites; p, germination 

 of spores in host's gut. 



two sporozoites develop in the spore (o). Oocysts leave the host in 

 the faecal matter and become the source of infection. 



Body vermiform; schizogony in motile stage 



Family 1 Selenococcidiidae (p. 466) 



Body not vermiform 



Alternation of generations and of hosts . . Family 2 Aggregatidae (p. 466) 

 Only one host 



Gametocytes become associated early; many microgametes 



Family 3 Dobelliidae (p. 469) 



Gametocytes independent Family 4 Eimeriidae (p. 470) 



