26o FRESH-WATER BIOLOGY 



135 (136) 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- 

 FiG. 424. Chrysomotun; pulchra. X 400. spherical elevations. Flagellum scarcely equalling the 

 (After Stokes.) j^^^jy j^ length. Nucleus ovate. Contractile vacuoles 



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

 water. 



1^6(1^0 Flagclla two; two chromatophores. . . . Ochr omonas Wysoizki. 

 Representative species 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 ^39 



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. Mallomonas sp. X 500- (After Conn.) 



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



142 (145) Without chromatophores i43 



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



bodies Cyathomonas de Fromentel. 



Representative species. . Cya//jowf)wa5/rw«ca/ade Fromentel 1874. 



^.qrasr-^^ De Fromentel identified six or eight species, several of which are 



^^rg^'-r \ but slightly distinguished from each other. Length 12 to 20 /x. 



^«*^^ll r^*^^^ Fresh water. 



^^•JfiSaatf-^ Fig. 427. Cyalhomonas truncata. X 1200. (After Conn.) 



