252 FRESH-WATER BIOLOGY 



68 (63) Flagella two; body spindle-shaped when extended; chromatophores 



disk-shaped . Eutreptia Perty. 



Representative species. . . . . Eutreptia -Jridis Perty 1852. 



Body very changeable in form. Flagella equalling the 

 body in length. Eye-spot present. Length, when extended, 

 100 II. Pond water. 



Fig. 393. Eutreptia viridis. X soo. (After Conni) 



69 (76) With a thick cuticle or lorica 70 < 



70 (76) Lorica present. 71 



71(72) Lorica beaker-shaped or tube-shaped Ascoglena Stein. 



72 (71) Lorica spherical or cylindrical, smooth or spiny. 



Trachelomonas Ehrenberg . . 73 



73 (74i 75) Lorica smooth, colorless . . Trachelomonas lagenella Stein 1878. 



Lorica colorless, oval or elUptical, smooth. An obliquely projecting neck. 

 Length 20 to 35 ^. Fresh water. 



Fig. 394. 7 rachelomonas lagenella. X 600. (After Stein.) 



74 (73) 73) Lorica spinous, brown. 



Trachelomonas hispida Stein 1878. 



Lorica elongate-oval, with ends broadly rounded. Surface cov- 

 ered with minute, sharp-pointed spines. A short, tube-Uke neck 

 sometimes present. Brown in color. Length 30 to 36 ^ Pond 

 water, with other species of the genus. 



Fig. 39s. Trachelomonas hispida. X 400. (After Conn.) 



75 (73i 74) Lorica smooth, brown. Trachelomonas volvocina Ehrenberg 1833. 



Lorica nearly spherical, surface smooth, usually without a 

 neck. Flagellum long. Color brown. Diameter 30 m- Very 

 common among algae and other aquatic plants. 



Fig. 396. Trachelomonas volvocina. X 450. (After Edmondson.) 



76(69) With a thick cuticle but no lorica 77 



77 (78) Not flattened, ellipsoidal, with a pointed caudal process. 



Chloropeltis Stein. 



Representative species. 



Chloropeltis hispidula Stein 1878. 



Surface of the body ornamented with mi- 

 nute spines arranged in longitudinal rows. 

 Endoplasm green, with an eye-spot. Length 

 55 p. Fresh water, among diatoms. 



Fig. 397. Chloropeltis hispidula. X 600. (Alter 

 Conn.) 



78 (77) Flattened. ' 79 



