EUGREGARINARIA 



91 



In comparing this life cycle with that of Etmeria, given above, it 

 should be noted that in the gregarines, whose female gametes are 

 merogametes and numerous, the "spores" (small sporocysts each 

 containing several sporozoites) are each the whole product of a zygote 



Fig. 78. A diagram of the life cycle of Monocystis. A, Trophozoite adhering 

 to the seminal funnel of the host. B, Encysted syzygy. C, Formation of 

 gametes. D, Conjugation. E, Encystment of zygotes. F, Multiplication of 

 nuclei of the same. G, Formation of sporozoites (only four of the eight are 

 shown). H, Release of sporozoites in intestines of new host. I, Infestation of 

 sperm morula, ext. external coat of gamocyst; gam. gametes; int. internal 

 coat of gamocyst; res. residual protoplasm; spc. cells of sperm morula; spe. 

 tails of withered spermatozoa adhering to parasite; spz. sporozoites. 



(i.e. are oocysts), whereas in the coccidians, where the female gamete 

 is a hologamete, the zygote forms, by means of a generation of 

 sporoblasts, several such spores in its oocyst. 



