FLAGELLATE PROTOZOA (MASTIGOPHORA) 265 



167 (166) Body not enclosed by a lorica Carter ia 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 chromatophores; occasionally a colored eye-spot. 



Ellipsoidal, two contractile vacuoles. . Polytoma Ehrenberg. 



Representative species Polytoma uvella 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 

 Representative species. . . . 



Treymnia Stokes. 

 Trentonia jiagellata Stokes 1886. 



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- 



nc. 441. Trentonta jiagellata. X 400. (After Stokes.; merous green chromatophores. Length 



60 AX. Pond water. 



174 (173) Chromatophores few, sometimes wanting 175 



175 (176) Spherical or elliptical, with one large chromatophoro. An eye- 

 spot present Chlaviydomoiias Ehrenberg. 



Representative species. 



Chlamydomonas pulvisculus Ehrenberg 1883. 



Fig. 442. Chlamydomcnas pulvhculu'i. X looo (.\(tcr Coon.) 



