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HANDBOOK OF PROTOZOOLOGY 



The sporozoites escape from the spores and make their way 

 through the micropyle of the oocyst into the gut lumen (p). 

 By active movement they reach the gut epithelium and enter 

 the host cells (a). These schizonts grow into large rounded 

 bodies. The nucleus multiplies in number. The newly formed 

 nuclei move to the body surface, and each becomes surrounded 



Fig. 109 Scheme of development of Eimeria schuhergi. X400 

 (After Schaudinn). 

 a, entrance of a sporozoite in the gut epithelium of host and growth of 

 schizont; b, three stages in schizogony to form merozoites, which repeat schizo- 

 gony or; c, become macro- and micro-gametocyte; d, e, formation of macro- 

 gamete; f-h, formation of microgametes; i, mature gametes; j, k, fertilization; 

 1-n, stages in spore formation; o, oocyst containing four mature spores, each 

 with two sporozoites; p, germination of spores. 



by a small mass of cytoplasm, forming what is called a mero- 

 zoite. When the host cells rupture, the merozoites are set 



