152 



PROTOZOOLOGY 



Among the Sporozoa, anisogamy is of common occurrence. In 

 Coccidia, the process was well studied in Eimeria schuhergi (Fig. 

 215), Aggregata eberthi (Fig. 217), Adelea ovata (Fig. 222), etc., and 

 the resulting products are the oocysts (zygotes) in which the spores 



Fig. 74. The life-cycle of Stephanosphaera pluvialis (Hieronymus). 

 a-e, asexual reproduction; f-m, sexual reproduction. 



or sporozoites develop. Similarly in Haemosporidia such as Plasmo- 

 dium vivax (Fig. 225), anisogamy results in the formation of the 

 ookinetes or motile zygotes which give rise to a large number of 

 sporozoites. Among Myxosporidia, a complete information as to 

 how the initiation of sporogony is associated with sexual reproduc- 



