260 



FRESH-WATER BIOLOGY 



135 ( J 3 6 ) Flagellum single; two chromatophores. . Chromulina Cienkowsky. 



Chrysomonas Stein is very closely related to this 

 genus. Under the name Chrysomonas pulchra Stokes 

 describes a species as follows: Body elongate-ovate or 

 obovate, somewhat flexible, three times as long as 

 broad, tapering and slightly constricted posteriorly, 

 curved toward one side anteriorly. Frontal border ob- 

 liquely excavate. Surface covered with minute hemi- 

 X 400. spherical elevations. Flagellum scarcely equalling the 

 body in length. Nucleus ovate. Contractile vacuoles 

 two, anterior. Length 35 to 40 M- Color green. Marsh 

 water. 



FlG. 424. Chrysomonas pukhra. 

 (After Stokes.) 



136 (135) Flagella, two; two chromatophores. 

 Representative species 



. . Ochromonas Wysotzki. 

 Ochromonas sp. 



Species not identified. 



FIG. 425. Ochromonas sp. X 1000. (After Conn.) 



137 (134) Body enclosed by a membrane or lorica 138 



138(157) With a membrane 139 



139 (146) Not forming colonies 140 



140 (141) With a close-fitting membrane of plates; flagellum single. 



Mallomonas Perty. 

 Representative species Mallomonas sp. 



Body elongated, enclosed by a membrane of overlapping 

 plates which bear long, slender spines. Two elongated, yel- 

 lowish-green chromatophores are within the body. 



Species not determined. 



FIG. 426. Mattomonas sp. x 500. (After Conn.) 



141 (140) With a firm cuticle; two flagella 142 



142 (145) Without chromatophores 143 



143 (144) Body oval, truncate or concave anteriorly, enclosing refractive 



bodies Cyathomonas de Fromentel. 



Representative species. . Cyathomonas truncata fe Fromentel 1874. 



De Fromentel identified six or eight species, several of which are 

 but slightly distinguished from each other. Length 12 to 20/1. 

 Fresh water. 



FIG. 427. Cyathomonas truncata. X 1200. (After Conn.) 



