FLAGELLATE PROTOZOA (MASTIGOPHORA) 265 



167 (166) Body not enclosed by a lorica Carleria Diesing. 



168 (165) Flagella usually two; often forming colonies 169 



169 (180) Not forming colonies 170 



170 (177) Body with closely attached cuticle 171 



171 (172) Usually without chroma tophores; occasionally a colored eye-spot. 



Ellipsoidal, two contractile vacuoles. . Polytoma Ehrenberg. 

 Representative species. . . Polytoma woella Ehrenberg 1838. 



Flagella two, equal, longer than the body, both extending forward 

 with loop-like flexures at their bases. Endoplasm usually granular. 

 Length 20 to 30 m. Animal macerations. 



Fig. 440. Polytoma uvella. X iioo. (After Conn.) 



172(171) With chromatophores. 



173 



173 (174) Chromatophores numerous; one flagellum trailing. 



Trent onia Stokes. 

 Representative species Trentoniaflagellata Stokes 1&86. 



Body ovate, the anterior border oblique 

 and somewhat bilobate, the posterior ex- 

 tremity obtusely pointed. Flagella sub- 

 equal in length, one extending forward, 

 often rapidly and spirally vibrating. 

 Mouth and pharynx conspicuous. Nu- 

 FiG. 441. Trenlonia flagellala. X 400. (After Stokes.) merous green chromatophores. Length 



60 li. Pond water. 



174 (173) Chromatophores few, sometimes wanting 175 



17s (176) Spherical or eUiptical, with one large chromatophore. An eye- 

 spot present . Chlamydomonas Ehrenberg. 



Representative species. 



Chlamydomonas pulvisculus Ehrenberg 1883. 



Fig. 443. Chlamydomonas pulvisculus, X looo. (After Conn.) 



