EUGLENOIDINA 211 



usually an elongated form; there is a cytopharynx and cytostome, 

 the former being connected with the reservoir of contractile 

 vacuoles; without stigma; flagellum usually straight and its free 

 end vibrates in a characteristic manner; asexual reproduction by 

 longitudinal fission. 



Genus Astasia Dujardin. Body plastic, although ordinarily 

 elongate; fresh water or endoparasitic (?) in Cyclops, etc. Several 

 species. 



A. klehsi Lemmermann (Fig. 97, a). Spindle-form; posterior 

 portion drawn out; flagellum as long as body; plastic; paramylon 

 bodies oval; 50-60ai by 13-20^; stagnant water. 



Genus Urceolus Mereschkowsky {Phialonema Stein). Body 

 colorless; plastic; flask-shaped; striated; a funnel-like neck; 

 posterior region stout; a single flagellum protrudes from funnel 

 and reaches inward the posterior third of body; fresh or salt 

 water. 



U. cyclostomus (Stein) (Figs. 8, /; 97, h). 25-50yu long; fresh 

 water. 



U. sahulosus (Stokes) (Fig. 97, c). Spindle-form ; surf ace covered 

 with minute sand-grains; about 58^ long; fresh water. 



Genus Peranema Dujardin. Elongate with a broad, rounded 

 or truncate posterior end during locomotion; highly plastic 

 when stationary; delicate pellicle shows a fine striation; flagellum 

 long, tapers toward free end and vibrates; nucleus central; con- 

 tractile vacuoles; saprozoic and holozoic; in stagnant water; 

 often in hay infusion. 



P. trichophorum (Ehrenberg) (Figs. 26; 97, d). 20-70/i long; 

 very common. 



P. granulijera Penard. Much smaller, 8-15/x long; spherical or 

 elongate; pellicle granulated; standing water. 



Genus Petalomonas Stein. Colorless; constant in form; pellicle 

 often with longitudinal keels on one side; a single flagellum; 

 holozoic or saprozoic; cytostome at anterior end; cytopharynx 

 fairly deep; in fresh water, rich in vegetable matter. Many 

 species. 



P. mediocanellata S. (Fig. 97, e). Ovoid with longitudinal fur- 

 row; flagellum about as long as body; 22-23ai long. 



Genus Menoidium Perty. Rigid body, more or less curved; 

 peUicle striated; a single flagellum; fresh water. 



M. incurvum (Fresenius) (Figs. 24, d; 64; 97,/). Crescentic cyl- 



