476 



PROTOZOOLOGY 



Genus Lankesterella Labbe. Oocyst produces 32 or more sporo- 

 zoites directly without spore-formation; in endothelial cells of cold- 

 Ijlooded vertebrates; mature sporozoites enter erythrocytes in which 

 they are transmitted to a new host individual by bloodsucking in- 

 vertebrates. 



L. minima (Chaussat) (Fig. 221, /). In frogs; transmitted by 

 the leech (Placobdella marginata); frog acquires infection through 

 introduction of sporozoites by a leech; sporozoites make their way 



Fig. 221. a, Isospora felis, X930 (Wenyon); b, /. lieberkuhni, X660 

 (Laveran and Mesnil); c, Cyclosporn caryolytica, X1330 (Schaudinn); 

 d, Dorisiella scolelepidis, oocyst with two spores, X1400 (Ray); e, f, 

 Caryospora simplex, X800 (Leger); g-i, Cryptosporidium maris (g, h, 

 oocysts; i, emergence of four sporozoites), XlOBO (Tyzzer); j, Pfeif- 

 ferinella ellipsoides, X1330 (Wasielewski) ; k, P. impudica, X800 (Leger 

 and Hollande); 1, Lankesterella minima, a mature cyst in endothelial cell, 

 XlOOO (Xoller); m, Barrouxia ornata, X1330 (Schneider); n. Echinospora 

 labbei, XlOOO (L^ger). 



into the blood capillaries of various organs; there they enter endo- 

 thelial cells; schizogony produces numerous merozoites which bring 

 about infection of many host cells; finally macro- and micro-gameto- 

 C3^tes are formed; anisogamy produces zygotes which transform into 

 oocysts, in which a number of sporozoites develop; these sporozoites 



