150 SPOEOZOA. 



the male the nucleus is central, oval or quadrangular in form, 

 and always compact. In the female the nucleus may often 

 be polar, and always contains a definite karyosome in its centre. 

 In the capillary circulation occurs the endoglobular cycle. 

 A merozoite invades the red corpuscle, grows into a schizont, 

 and by twice repeated binary division forms a macrocyst 

 containing four large gregariniform merozoites. These mero- 

 zoites invade the endothelial cells of the lungs and hver and 

 produce microcysts, each containing eight leishmaniform 

 merozoites. The microcysts hberate the merozoites either in 

 the interstices of the tissues or in the protoplasm of the endo- 

 thehal cell itself. This second schizogonic cycle has been 

 designated as the endothelial cycle. The leishmaniform. 

 merozoites may invade either the red corpuscles, where they 

 undergo binary divisions again, or the endothehal cells, where 

 they again become microcysts. It is not known from what 

 particular forms the gametocysts are derived. Sporogony 

 completely unknown. 



Dimensions. — Gametocytes measure 5-11 fx by 1-5-2-5 [x. 

 Macrocysts measure 13-15 /x by 8-1 Oju,; macromerozoites 

 measure 8-1 l/i. by 2-5-3jLt. Leishmaniform merozoites: 

 roundish 1-5-3 ju, in diameter, fusiform 3-5^ by 1-1-5 /x. 



Remarks. — The lack of karyolitic action on the part of the 

 parasite and the occm-rence of endoglobular schizogony makes 

 the organism a remarkable transitional form between H8em,o- 

 gregarina and the previously known species of Karyolysus. 

 The differentiation of the gametocytes and the occurrence of 

 a paranuclear body and specially differentiated polar area in 

 the gametocytes and the pecuhar form and structure of the 

 micromerozoites are other characteristic features of the 

 species. 



Habitat. — Red blood- corpuscles and endothelial cells of the 

 liver and lungs of Calotes versicolor Daud. subsp. major Bl3^h : 

 Portuguese India, Nova Goa. 



II. Suborder EIMERIDEA Leger, 1911. 



The schizonts develop into micro- and macrogametocytes 

 which are similar in size and develop independently of one 

 another. The microgametocyte produces a relatively large 

 number (six or more) of microgametes. The motionless zygote 

 secretes a resistent oocyst, which does not increase in size. 

 The asexual and the sexual cycles occur in the same host. 



Various schemes of classification of the suborder have been 

 proposed. It is generally admitted that the composition of the 

 mature oocyst, viz., the number of sporocysts and sporozoites 



