FLAGELLATE PROTOZOA (MASTIGOPHORA) 249 



45 (44) Body spiral, elongated Spiromonas Perty. 



Representative species Spiromonas angusta Dujardin 1841. 



Body five or six times as long as broad. Fla- 

 gella subequal, as long as the body, one directed 

 forward; body sometimes temporarily attached 

 by one. Length 10 /* Hay infusions. 



FIG. 382. Spiromonas angusta. X 1000. (After Conn.) 

 There is doubt as to the identity of Conn's form. 



46 (43) Body neither spiral nor oblique 47 



47 (48) Kidney-shaped to spherical; flagella arising from a ventral depres- 

 sion, one trailing. Food absorbed by a dorsal vacuole. 



Pleuromonas Perty. 

 Representative species ...... Pleuromonas j oceans Perty 1852. 



Body kidney-shaped, very small; sometimes attached by the pos- 

 terior flagellum. Contractile vacuole anterior; nucleus posterior. 



Length 5 to 9 M- Stagnant water and infusions. Movements 

 jerking and leaping. 



FIG. 383. Pleuromonas jaculans. X 1000. (After Conn.) 



48 (47) Pear-shaped to spindle-shaped; flagella arising from the anterior 



end, one trailing. Food not taken in by a dorsal vacuole. 



Heteromita Dujardin. 

 Representative species Heteromita ovata Dujardin 1841. 



Body ovate, widest posteriorly. Flagella unequal, the 

 trailing one twice as long as the anterior one. Length 

 25 to 40 M- River water with aquatic plants. 



FIG. 384. Heteromita ovata. X 500. (After Conn.) 



49 (38) Flagella usually numerous, frequently arranged in groups. 



Order Phytomastigida . . 50 



50 (53) Flagella two in number 51 



51 (52) Body expanded into two wings; flagella long. 



Trepomonas Dujardin. 

 Representative species Trepomonas agilis Dujardin 1841. 



Very irregular in shape, different appearances being presented 

 from different points of view. The broad, wing-like lateral lobes 

 curve backward nearly to the middle of the body. Length 20 /* 

 Pond water. 



FIG. 385. Trepomonas agilis. X 450. (After Conn.) 



