294 PROTOZOOLOGY 



With rostellum Family 7 Oxymonadidae (p. 301) 



Flagellar cords on body surface 



Family 8 Dinenymphidae (p. 302) 



With cresta Family 9 Devescovinidae (p. 303) 



With undulating membrane. . . .Family 10 Trichomonadidae (p. 308) 



Family 1 Trimastigidae Kent 



Genus Trimastix Kent. Ovate or pyriform; naked; free-swimming; 

 with a laterally produced membranous border; 3 flagella (1 anterior 

 flagellum vibrating, 2 trailing) ; salt water. 



Fig. 



133. a, Trimastix marina, X1250 (Kent); b, Dallingeria drysdali, 

 X2000 (Kent); c, Macromastix lapsa, X1500 (Stokes). 



T. marina K. (Fig. 133, a). About 18/x long; salt water. 



Genus Dallingeria Kent. Free-Swimming or attached; with trail- 

 ing flagella; body small; with drawn-out anterior end; fresh water 

 with decomposed organic matter. 



D. drysdali K. (Fig. 133, 6). Small; elongate oval; less than 6m 

 long; stagnant water. 



Genus Macromastix Stokes. Free-swimming, somewhat like 

 Dallingeria, but anterior region not constricted; 3 flagella from an- 

 terior end; one contractile vacuole; fresh water. 



M. lapsa S. (Fig. 133, c). Ovoid; 5.5/i long; anterior flagellum 1/2 

 and trailing flagella 2-3 times body length; pond water. 



