384 I'ROTOZOOLOGY 



ducts; spores elongate ovoid, with 8 sporozoites; in gut of 

 ephemcrid larvae. 



E. ensis Z. (Fig. 175, k, I). Sporadins in syzygy 200-510^t long; 

 cysts 200-350^ in diameter; spores elongate ovoid; in gut of 

 larvae of Caenis sp. 



Family 2 Rhynchocystidae Bhatia 



Trophozoites ovoid, spherical or elongate, with a conical or 

 cylindro-conical trunk at anterior end; solitary; spore biconical, 

 with 8 sporozoites. 



Genus Rhynchocystis Hesse. Trophozoites ovoid or cylindrical; 

 plastic epimerite, conical or cylindro-conical trunk; in seminal 

 vesicles of oligochaetes. Many species. 



R. pilosa Cuenot (Fig. 176, a). In seminal vesicles of Lumbricus 

 terrestris, L. castaneus and Helodrilus foetidus; 217ju by 25.5fi; 

 pellicle with close, longitudinal ridges from which arise 'hairs' 

 up to 40)U in length; endoplasm viscous, packed with oval (Sjjl by 

 2/i) zooamylum bodies; cysts ovoid, 95)U by 84yu; spores 13. 3^ 

 by 5m. 



R. porreda Schmidt (Fig. 176, b, c). In seminal vesicles of 

 Lumbricus rubellus and Helodrilus foetidus; extremely long with 

 an enlarged head; up to 2.5 mm. by 32-36^; sluggish; endoplasm 

 granulated, filled with oval (4/x by 2-3 ^t) paraglycogen grains; 

 nucleus 17-25^ in diameter; spores 27.7-28^ by 12jli; sporozoites 

 13-18m by 3-5^. 



Family 3 Zygocystidae Bhatia 



Trophozoites in association, spores biconical, with peculiar 

 thickenings at extremities; with 8 sporozoites; in seminal vesicles 

 or coelom of oligochaetes. 



Genus Zygocystis Stein. Sporadins pyriform, 2-3 in syzygy; 

 in seminal vesicles or coelom of oligochaetes. Several species. 



Z. wenrichi Troisi (Fig. 176, d, e). In seminal vesicles of 

 Lumbricus rubellus and Helodrilus foetidus; sporadins up to 1.5 

 mm. by 250/x in diameter; pellicle with longitudinal ridges which 

 become free and form a 'tuft of hairs' at the posterior end; cysts 

 500-800M by 300-500^; spores 28m by 13iu. 



Genus Pleurocystis Hesse. Trophozoites in longitudinal or 

 lateral association; spores biconical. One species. 



P. cuenoti H. (Fig. 176, /). In the ciHated seminal horn of 

 Helodrilus longus and H. caliginosus; 2 mm. by 300^; pellicle 



