64 



PROTOZOOLOGY 



ill 



thr 



WW 



extr 



•I I 



! 



trb 



P 

 trg 



trb 



rt 



en 



Fig. 22. a, b, cortical region of Frontonia leucas, with embedded and 

 extruded trichocysts (Tonniges) ; c, d, embedded and discharged tricho- 

 cysts of Dileptus anser, X4200 (Hayes); e, two extruded trichocysts of 

 Paramecium caudatutn, X1530. ci, cilium; ec, ectoplasm; en, endo- 

 plasm; extr, extruded trichocyst; p, pellicle; rt, root of trichocyst; 

 thr, thread of trichocyst; tr, trichocyst; trb, bulb of trichocyst; trg, 

 trichocyst granule. 



