HOLOTRICHA 



599 



or more vesicular micronuclei; a single macronucleus; in fresh water. 

 P. bursaria (Ehrenberg) (Fig. 283, d). Foot-shaped, somewhat 

 compressed; about lOO-lSOiuby 50-60ju; green, with zoochlorellae as 

 symbionts; micro nucleus compact; 2 contractile vacuoles; in fresh 

 water. 



Fig. 283. Semi-diagrammatic drawings of nine species of Paramecium 

 in oral surface view, showing distinguishing characteristics taken from 

 fresh and stained specimens, X230 (several authors), a, P. caudatum; 

 b, P. aurelia; c, P. multurvicronucleahun; d, P. hxirsaria; e, P. putrinum; 

 f, P. calkinsi; g, P. trichium; h, P. -pohjcaryum; i, P. woodruffi. 



P. putrinum ClaparMe and Lachmann (Fig. 283, e). Similar to P. 

 bursaria, but a single contractile vacuole and an elongated macronu- 

 cleus; no zoochlorellae; 80-150^ long; in fresh water. 



