SPOROZOA, GREGARINIDA 455 



S. provincialis L. (Fig. 210, m, n). Sporadins 1-2 mm. long; cysts 

 800m in diameter; in gut of larvae of Melolontha sp. and Rhizotrogus 

 sp. 



Genus Bothriopsis Schneider. Epimerite sessile, small, oval, with 

 6 or more filamentous processes directed upward; spores biconical; 

 cysts spherical. 



B. histrio S. (Fig. 210, o). Epimerite with 6 filaments, 80-90m 

 long; cysts 400-500^ long; spores 7.2/i by 5m; in gut of Hydaticus 

 sp. 



Genus Coleorhjmchus Labbe. Epimerite discoid, lower border 

 over deutomerite; spores biconical. 



C. heros (Schneider) (Fig. 210, p-r). Sporadins 2-3 mm. long; in 

 gut of Nepa cinerea. 



Genus Legeria Labb6. Protomerite wider than deutomerite; 

 epimerite unknown; cysts without duct; spores cylindro-biconical. 



L. agilis (Schneider) (Fig. 210, s). In gut of the larvae of Colym- 

 betes sp. 



Genus Phialoides Labbe. Epimerite a cushion set peripherally 

 with stout teeth, surrounded by a wider collar; with a long neck; 

 cysts spherical, without ducts; spores biconical. 



P. ornata (Leger) (Fig. 210, t-v). Sporadins 500/x long; cysts 

 300-400m in diameter; spores 10.5/i by 6.7m; in gut of larvae of 

 Hydrophilus piceus. 



Genus Geneiorh3nichus Schneider. Epimerite a tuft of short 

 bristles at end of neck; spores cylindrical. 



G. aeschnae Crawley (Fig. 210, w). Sporadins 420m long; cysts 

 and spores unknown; in Aeschna constricta. 



Family 13 Porosporidae Leger 



When naked or well-protected sporozoites enter the stomach 

 and midgut of a specific crustacean host, they develop into typi- 

 cal cephaline gregarines; 1, 2, or more sporadins become associat- 

 ed and encyst. Repeated nuclear and cytoplasmic division re- 

 sults in formation of an enormous number of gymnospores in hind- 

 gut. Some observers consider this change as schizogony, and hence 

 include the family in the suborder Schizogregarinaria. When the 

 gymnospores are voided in the faeces of crustaceans and come in 

 contact with moUuscan host, they enter, or are taken in by phago- 

 cytosis of, the epithelial cells of the gills, mantle or digestive system. 

 These gymnospores are especially found in abundance in the 

 lacunae of the gills. Presently they become paired and fuse (Hatt) ; 



