746 



PROTOZOOLOGY 



right of the median plane, which leads into peristome cavity and 

 gives rise dorsally to a diagonal groove; right edge of cytostome bears 

 a ciliated area, but no protruding membrane as in Bryophrya (p. 

 747); macronucleus spherical or oval, central; a compact micronu- 

 cleus; a contractile vacuole terminal; in fresh water. Many species. 

 Burt (1940) made a comparative study of five species, which are 

 mentioned here. 



C. cucullus M. (Fig. 318, a). 40-110/x long; anterior keel with eight 



Fig. 318. a, Colpoda cucullus; h, C. inflata; c, C. maupasi; d, C. aspera; 

 e, C. steini, all X330 (Burt); f, g, Tillina magna, X100 (Bresslau); h, T. 

 canalifera, X330 (Turner); i, Bresslaua vorax, X100 (Kahl); j, Bryophrya 

 bavariensis, X280 (Kahl); k, Woodruffia rostrata, XI 90 (Kahl). 



to 10 indentations; 29-34 ciliary grooves; cilia mostly paired; macro- 

 nucleus with a stellate endosome; trichocysts rod-form; usually with 

 abundant food vacuoles; in fresh water with decaying plants. 



C. inflata (Stokes) (Fig. 318, 6). 35-90 M long; anterior keel with 6- 

 8 indentations; number of ciliary grooves (or meridians) 21-24; cilia 

 mostly in pairs; in fresh water among vegetation. 



C. maupasi Enriques (Fig. 318, c). 35-90/x long; cytostome about 



