258 PROTOZOOLOGY 



Family 1 Chromulinidae Engler 



Minute forms, naked or with sculptured shell; with a single flagel- 

 lum; often with rhizopodia; a few colonial; free-swimming or at- 

 tached. 



Genus Chromulina Cienkowski. Oval; round in cross-section; 

 amoeboid; 1-2 chromatophores ; palmella stage often large; in fresh 

 water. Numerous species. The presence of a large number of these 

 organisms gives a golden-brown color to the surface of the water. 

 Development (Doflein, 1923); species (Doflein, 1921, 1922; Schiller, 

 1929; Pascher, 1929; Conrad, 1930). 



C. pascheri Hofeneder (Fig. 104, a, b). 15-20/* in diameter. 



Genus Pseudochromulina Doflein. Spheroid body amoeboid; cyto- 

 plasm granulated; two contractile vacuoles anterior; a single flagel- 

 lum about the body length; a yellow tray-like chromatophore with 

 upturned edge; stigma and pyrenoid absent; nucleus central; cyst 

 ovoid, with asymmetrical siliceous wall with an aperture tube (Do- 

 flein, 1921). 



P. asymmetrica D. Body 3-4 /* in diameter; cytoplasm with fat and 

 probably leucosin; cyst 4/* by 3/*; aperture tube about l/i; fresh 

 water (Doflein, 1921). 



Genus Chrysamoeba Klebs. Body naked; flagellate stage ovoid, 

 with 2 chromatophores, sometimes slender pseudopodia at the same 

 time; flagellum may be lost and the organism becomes amoeboid, 

 resembling Rhizochrysis (p. 267) ; standing fresh water. 



C. radians K. (Fig. 105, a, b). Flagellated form measures 8/x by 

 3.5/*; amoeboid stage about 8-10/* by 3-4/x, with 10-20/x long radiat- 

 ing pseudopodia; cyst 7/* in diameter (Doflein, 1922). 



Genus Chrysapsis Pascher. Solitary; plastic or rigid; chromato- 

 phore diffused or branching; with stigma; amoeboid movement; 

 holophytic, holozoic; fresh water. Several species. 



C. sageneF. (Fig. 104, c). Anterior region actively plastic; stigma 

 small; 8-14m long; flagellum about 30/* long. 



Genus Chrysococcus Klebs. Shell spheroidal or ovoidal, smooth 

 or sculptured and often brown-colored; through an opening a flagel- 

 lum protrudes; 1-2 chromatophores; one of the daughter individuals 

 formed by binary fission leaves the parent shell and forms a new one ; 

 fresh water. Lackey (1938) found several species in Scioto River, 

 Ohio. 



C. ornatus Pascher (Fig. 104, d). 14-16/* by 7-10/*. 



Genus Mallomonas Perty (Pseudomallomonas Chodat). Body 

 elongated; with silicious scales and often spines; 2 chromatophores 



