588 PROTOZOOLOGY 



C. parvum T. In the glands of small intestine of the mouse; oocysts 

 with 4 sporozoites, 4.5/* in diameter (Tyzzer, 1912). 



Genus Pfeifferinella Wasielewski. Macrogamete with a "recep- 

 tion tubule" by which microgamete enters; oocyst produces directly 

 8 sporozoites. 



P. ellipsoidcs W. (Fig. 252, j). In the liver of Planorbis corneus; 

 oocysts oval, 13-15/* long. 



P. impudica Leger and Hollande (Fig. 252, k). In the liver of 

 Limax marginatus; oocysts ovoid, 20/* by 10/*. 



Genus Lankesterella Labbe. Oocyst produces 32 or more sporo- 

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

 blooded vertebrates; mature sporozoites enter erythrocytes in which 

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

 vertebrates. 



L. minima (Chaussat) (Fig. 252, I). In frogs; transmitted by 

 the leech (Placobdella marginata) ; frog acquires infection through 

 introduction of sporozoites by a leech; sporozoites make their way 

 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- 

 cytes are formed ; anisogamy produces zygotes which transform into 

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

 are set free upon disintegration of cyst wall in the blood plasma and 

 enter erythrocytes (Noller) ; oocyst oval, about 33/* by 23/*. 



Genus Schellackia Reichenow (Tyzzeria Allen). Oocyst spherical 

 with 8 sporozoites, without spore membrane; in the intestine of birds 

 and lizards. 



S. bolivari R. In the mid-gut of the lizards, Acanthodactylus vul- 

 garis and Psammodromus hispanicus; development somewhat simi- 

 lar to that of Eimeria schubergi (Fig. 243) ; oocysts spherical, 15-19/* 

 in diameter, with 8 sporozoites (Reichenow, 1919). 



S. perniciosa (Allen). In the small intestine of Anas domesticus; 

 oocysts 10-13.3/* by 9-10.8/*; highly pathogenic. 



Genus Barrouxia Schneider. Oocyst with numerous spores, each 

 with a single sporozoite; spore membrane uni- or bi-valve, with or 

 without caudal prolongation. Development (Schellack and Reiche- 

 now, 1913). 



B. ornata S. (Fig. 252, m). In gut of Nepa cinerea; oocysts spheri- 

 cal, 34-37/* in diameter, with many spores; spore with one sporozoite 

 and bivalve shell, 17-20/* by 7-10/*. 



Genus Echinospora Leger. Oocyst with 4-8 spores, each with a 

 sporozoite; endospore with many small spinous projections. 



