36 PROTOZOA 



1. Cyathomonas Fromentel. Body colorless, ovoid, flattened, with 

 obliquely truncated forward end, with 2 flagella of nearly equal length; 

 parallel with the anterior border is a row of highly retractile bodies: 

 1 species. 



C. truncata (Fresenius) (Fig. 44). Length .023 mm.: in fresh 

 water and infusions. 



2. Chilomonas Ehrenberg. Body colorless, oval, compressed; for- 

 ward end obliquely notched, with two equally long flagella: 2 species; 

 in fresh water and infusions. 



Fig. 44 Fig. 45 Fig. 4G 



Fig. 44 — CyatJiomonas truncata (Coun). Fig. 45 — Chilomnnas Paramecium (Conn), 

 Fig. 46—Chlamydumonas pulvisculus (Conn). 



C. Paramecium Ehr. (Fig. 45). Body ellipsoid; length .03 mm.: 

 very common. 



3. Cryptomonas Ehrenberg. Like Chilomonas, but with 2 green or 

 brown chromatophores : 2 species; in fresh and salt water. 



C. ovata Ehr. Length .03 mm.: in fresh water, to which it may 

 give a fishy taste. 



Suborder 2. CHLAMYDOMONADINA. 



Body gi^een in color with 2 or 4 flagella and usually a firm cuticula 

 or shell within which division takes place: 2 families. 



Family CHLAMYDOMONADIDAE. 



Cuticula very delicate with no large pores: 7 genera. 



1. Chlamydomonas* Ehrenberg. Body spherical to cylindrical 

 with 2 flagella and an eye-spot, a delicate shell, prominent chromato- 

 phores and 2 contractile vacuoles: about 6 species; in fresh water. 



C. pulvisculus Ehr. (Fig. 46). Body spherical, about .02 mm. in 

 diameter: in fresh water, to which it gives an oily flavor. 



2. Spondylomorum Ehrenberg. Colony of 16 cells in 4 alternating 

 rows, each cell witli 4 flagella: 1 species. 



S. quaternarium Ehr. Diameter of colony .05 mm.: in fresh water. 



3. PoLYTOMA Ehrenberg. Body ellipsoid witli a delicate shell and 

 2 flagella, colorless, occasionally with an eye-spot; 2 contractile vacuoles; 



* See "Chlamydomonas and Its Effect on Water Supplies," by G. C. Whipple, 

 Trans. Am. Micro, Soc, Vol. 21, p. 97, 1900. 



