714 PROTOZOOLOGY 



plasm granulated; body 70m long, up to 150m (Kahl) ; salt water. 



L. coronata C. and L. (Fig. 305, c). Large; neck extensible; body 

 form variable, but usually with bluntly rounded posterior end; endo- 

 plasm appears dark; striae spiral; 85-100/x long; salt and brackish 

 water. 



Genus Enchelys Hill. Flask-shape; anterior end obliquely trun- 

 cate; cytostome slit-like, rarely round; fresh or salt water. Several 

 species (Faur6-Fremiet, 1944). 



E. curvilata (Smith) (Fig. 305, d). Elongate ovoid; posterior end 

 rounded; longitudinal striation; macronucleus band-form; contrac- 

 tile vacuole terminal; endoplasm yellowish, granulated; about 150m 

 long; fresh water among algae. 



Genus Crobylura Andre. Body when extended spindle-form, with 

 truncate ends; when contracted, thimble-form; cilia short and thick; 

 several long caudal cilia; slit-like cytostome at anterior end; no 

 apparent cytopharynx; macronucleus irregularly rounded, hard to 

 stain; micro nucleus not observed; contractile vacuole latero-pos- 

 terior; fresh water. One species. 



C. pelagica A. (Fig. 305, e). Body 65-95m long; in freshwater 

 plankton. 



Genus Microregma Kahl. Small, ovoid; dorsal side convex; 

 ventral side flat; with a small slit-like cytostome near anterior end; 

 with or without caudal bristle; fresh or salt water. 



M. {Enchelys) auduboni (Smith) (Fig. 305, /). Body plastic; 

 coarsely ciliated; caudal bristle thin; cytostome at anterior end, 

 surrounded by longer cilia; cytopharynx small with trichocysts; 

 round macronucleus central; contractile vacuole near posterior end; 

 40-55m ; fresh water. 



Genus Chaenea Quennerstedt. Elongate; anterior end drawn 

 out into a narrow truncated 'head'; but without any ring furrow; 

 'head' spirally or longitudinally furrowed; often with longer cilia 

 directed anteriorly; cytostome terminal, not lateral; cytopharynx 

 with trichocysts; body striation meridional, or slightly right spiral; 

 macronucleus often distributed; fresh or salt water. 



C. limicola Lauterborn (Fig. 305, g). Anterior half of body broad; 

 posterior end drawn out into a point; contractile; cytopharynx with 

 trichocysts; many trichocysts in endoplasm; contractile vacuoles 

 in a row; 130-150m long; stagnant fresh water. 



Genus Pithothorax Kahl. Slender, barrel-shaped; with firm pellicle; 

 a fairly long caudal bristle - , contractile vacuole in posterior half ; cilia- 

 tion coarse and not over entire body surface; resembles Coleps; fresh 

 water. 



