250 FRESH-WATER BIOLOGY 



52 (51) Body not laterally expanded, sometimes attached by a stalk. Flagella 



arising from the anterior end. . . AmpJiimojias Du}a.rdm. 



Representative species Amphimonas globosa Kent 1880. 



Body subspherical, attached by a filamentous pedicel. Flagella equal, twice the 

 length of the body. Diameter 1 2 n. Pond water. 



Fig. 386. Amphimonas globosa. X 875, (After Kent.) 



Conn reports a form, found abundantly in the fresh waters of Connecticut, which 

 he assigns to this genus, with some doubt. Although never attached by a pedicel, 

 the two equal flagella would seem to place it here. 



53 (50) Flagella four in number 54 



54(55) With a deep, vertical furrow Collodictyon Ca.TiGT. 



55 (54) Without a vertical furrow 56 



56 (57) With three flagella directed forward, one trailing. Body pear-shaped, 



rounded in front, acute behind. . Trichomastix Blochmann. 

 Representative species Trichomastix sp. 



American species observed have not been de- 

 termined. 



Fig. 387. Trichomastix sp. X 7S0. (After Conn.) 



57 (56) With all four flagella directed forward 58 



58 (59) Body ellipsoidal, with two thread-like processes at the posterior 



end Hexamitd Dujardin. 



Representative species Hexamita inflata Dujardin 1838. 



Body plastic, posterior end bifid, giving rise to the trailing, flagella-like 

 processes by means of which it may be temporarily fixed. Length 10 to 

 15 ti. Pond water and infusions. 



Fig. 388. Hexamita inflata. X 875. (After Coon.) 



