Three generations of schisonts in the life cycle of Eimeria akeriana, the intestinal parasite of Meriones blackleri, were determined. Gametogony begins in 94 hours, the first oocysts discharge in 5.5--6 days and lasts 14.5 to 15 days after the oocyst administration. A cytochemical study of the distribution of the nucleic acids, proteins and amylopectin at the stages of endogenous development of E. akeriana has revealed a considerable similarity among the parasites of Eimeria though each type is characterized by some cytochemical peculiarities.