Chapter 33 

 Order 1 Holotricha Stein (continued) 



Suborder 2 Gymnostomata Biitschli (continued) 

 Tribe 2 Pleurostomata ScheAviakoff 



Cytostome on convex ventral surface. 



Cytostome a long slit Family 1 Amphileptidae 



Cytostome round, at base of trichocyst-bearing neck 



Family 2 Tracheliidae (p. 725) 



Cytostome on concave ventral side Family 3 Loxodidae (p. 727) 



Family 1 Amphileptidae Schouteden 



Genus Amphileptus Ehrenberg. Flask-shaped; somewhat com- 

 pressed; ciliation uniform and complete; slit-like cytostome not 

 reaching the middle of body, without trichocyst-borders; many con- 

 tractile vacuoles; 2 or more macro nuclei; fresh or salt water. 



A. claparedei Stein (A. meleagris Claparede and Lachmann) (Fig. 

 309, a). Slightly flattened; broadly flask-shaped; with bluntly 

 pointed posterior and neck-like anterior end; cytostome about 2/5 

 from ventral margin; trichocysts indistinct; dorsal ciliary rows also 

 not distinct; contractile vacuoles irregularly distributed; 120-150ju 

 long; fresh and salt water, on stalks of Zoothamnium, Carchesium, 

 Epistylis, etc. 



A. branchiarum Wenrich (Fig. 309, b). On the integument and gills 

 of frog tadpoles; swimming individuals killed with iodine, 100-135/u 

 by 40-60/x (Wenrich, 1924). 



Genus Lionotus Wrzesniowski (Hemiophrys W.). Flask-shape; 

 elongate, flattened; anterior region neck-like; cilia only on right side; 

 without trichocyst-borders; cytostome with trichocysts; 1 (terminal) 

 or many (in 1-2 rows) contractile vacuoles; 2 macronuclei; 1 micro- 

 nucleus; fresh or salt water. 



L. fasciola (Ehrenberg) (Fig. 309, c). Elongate flask in form; hya- 

 line; with flattened neck and tail, both of which are moderately 

 contractile; posterior end bluntly rounded; without trichocysts; 

 neck stout, bent toward the dorsal side; cytostome a long slit; con- 

 tractile vacuole posterior; 2 spherical macronuclei between which a 

 micronucleus is located; 100/i long; fresh water and probably also in 

 salt water. 



Genus Loxophyllum Dujardin (Opisthodon Stein). Generally simi- 

 lar to Lionotus in appearance; but ventral side with a hyaline border, 

 reaching posterior end and bearing trichocysts; dorsal side with 



723 



