EIMBRIDEA. 157 



it contains, provides the most convenient diagnostic characters 

 for the differentiation of the genera : but different opinions 

 have been held regarding the basis upon which the genera 

 should be united into subfamiHes and famihes. Following 

 Ltihe (1906), Minchin (1912), Reichenow (1921) and Wenyon 

 (1926) arrange the genera into higher groups, mamly according 

 to the type of schizogony. Schneider (1881) and Leger (1911) 

 adopted the characters of the ripe oocyst as the basis for classi- 

 fication : but while Schneider and his followers, Biitschli 

 (1882), Labbe (1899) and Minchin (1903), arranged them 

 according to the number of sporocysts within the oocyst, 

 Leger (1900), foUowed by Mesnil (1903), Poche (1913), Doflein 

 (1916), Pinto (1928), and Noller (1928), classified them according 

 to the total number of sporozoites in the oocyst. 



Wenyon (1926) divides the suborder into six famihes, viz., 

 Selenococcidiidse, Cryptosporidiidse, Eimeriidse, Caryotrophidse, 

 Aggregatidae, and Lankesterelhdae. Reichenow (1929) re- 

 shuffled the genera among three famihes, and brought over 

 Dobelhdse from the Adeleidea and Leucocytozoidse from the 

 H^MOSPOKiDiA. Thus he classified the Eimeridea into five 

 famihes, viz., Selenococcidiidge, Aggregatidse, Dobellidse, 

 Eimerudse, and Leucocytozoidae. 



Hoare (1933), leaving out of consideration the famihes 

 Dobelhdse and Leucocytozoidse (which might as well be 

 included, as in Wenyon's classification), has proposed a modi- 

 fication of Leger's classification, in which the subfamilies 

 are distinguished from each other by the number of sporocysts 

 within the oocyst, while the genera within each subfamily 

 differ from one another in the number of sporozoites within 

 each sporocyst. The suborder is divided into two famihes : 

 (1) Selenococcidiidse and (2) Eimeriidse. The family Eimeriidse 

 is divided into six subfamilies. I have followed this classifica- 

 tion in this work. 



Identification Table of Families. 



1 (2). Body cylindrical or vermiform. Nuclear 



multiplication takes place in the extra- 

 cellular motile stage ; schizont becomes 

 rounded on entering an epithelial cell 

 and breaks up into eight merozoites, 

 which are set free into the limien of the 

 gut. Numerous microgametes formed 



from a microgametocyte. Fertiliza- [Leger & Duboscq. 



and sporogony unknown Selenococcidiidse * 



2 (1). Body not cylindrical or vermiform Eimeriidse Leger, em. 



[Hoare, p. 158. 



