220 PROTOZOOLOGY 



L. rostrata Hazen (Fig. 96, j). 5-1 2^ by 4-8^. 



Genus Diplostauron Korschikoff. Rectangular with raised cor- 

 ners; 2 equally long fiagella; chromatophore; one pyrenoid; stigma; 

 2 contractile vacuoles anterior; fresh water. 



D. pentagonium (Hazen) (Fig. 96, k). lO-lSju by 9-lOAt. 



Genus Gigantochloris Pascher. Unusually large form, equalling 

 in size a colony of Eudorina; flattened; oval in front view; elongate 

 ellipsoid in profile; membrane radially striated; 2 fiagella widely 

 apart, less than body length; chromatophore in network; numerous 

 pyrenoids; often without stigma; in woodland pools. 



G. permaxima P. (Fig. 96, 1). 70-150m by 40-80m by 25-50/x. 



Genus Gloeomonas Klebs. Broadly ovoid, nearly subspherical; 

 with a delicate membrane and a thin gelatinous envelope ; 2 fiagella 

 widely apart; chromatophores numerous, circular or oval discs; 

 pyrenoids (?); stigma; 2 contractile vacuoles anterior; freshwater. 



G. ovalis K. (Fig. 96, m). 38-42/^ by 23-33/1 ; gelatinous envelope 

 over 2/t thick. 



Genus Scourfieldia West. Whole body flattened; ovoid in front 

 view; membrane delicate; 2 fiagella 2-5 times body length; a chro- 

 matophore; without pyrenoid or stigma; contractile vacuole anter- 

 ior; nucleus central; fresh water. 



S. compla7iata W . (Fig. 96, n). 5.2-5.7/iby 4.4-4.6^; freshwater. 



Genus Thorakomonas Korschikoff. Flattened; somewhat irregu- 

 larly shaped or ellipsoid in front view; membrane thick, enclustered 

 with iron-bearing material, deep brown to black in color; proto- 

 plasmic body similar to that of Chlamydomonas; a chromatophore 

 with a pyrenoid; 2 contractile vacuoles; standing fresh water. 



T. sahulosa K. (Fig. 96, o). Up to 16m by 14m. 



Genus Coccomonas Stein. Shell smooth; globular; body not filling 

 intracapsular space; stigma; contractile vacuole; asexual reproduc- 

 tion into 4 individuals ; fresh water. 



C. orbicularis S. (Fig. 97, a). 18-25^ in diameter; fresh water. 



Genus Chlorogonium Ehrenberg. Fusiform; membrane thin and 

 adheres closely to protoplasmic body; plate-like chromatophores 

 usually present, sometimes ill-contoured; one or more pyrenoids; 

 numerous scattered contractile vacuoles; usually a stigma; a central 

 nucleus; asexual reproduction by 2 successive transverse fissions 

 during the motile phase; isogamy reported; fresh water. 



C. euchlorum E. (Fig. 97, 6). 25-7 Om by 4-1 5m; in stagnant water. 



Genus Phyllomonas Korschikoff. Extremely flattened ; membrane 

 delicate; 2 fiagella; chromatophore often faded or indistinct; numer- 

 ous pyrenoids; with or without stigma; many contractile vacuoles; 

 fresh water. 



