MORPHOLOGY 



59 



suture is separated at the point where the cytopyge is situated. 

 Usually 40-50 fibrils radiate outward from the cytostome (the 

 radial cytostomal fibrils). The pharyngeal portion is more com- 

 plex and consists of 1) the oesophageal network, 2) the motorium 

 and associated fibrils, 3) penniculus which is composed of 8 rows 

 of basal granules, thus forming a heavy band of cilia in the 



Fig. 19. Diagram of the cortical region of Paramecium multimicronu- 

 cleata, showing various organellae, x7300 (Lund), bg, basal granule; 

 c, cilia; et, tip of trichocyst; If, longitudinal fibril; p, pellicle; t, tricho- 

 cyst; tf, transverse fibril. 



cytopharynx, 4) oesophageal process, 5) paraoesophageal fibrils, 

 6) posterior neuromotor chain, and 7) postoesophageal fibrils. 

 Lund concludes that the so-called silverline system includes three 

 structures: namely, the peculiarly ridged pellicle; trichocysts 

 which have no fibrillar connections among them or with fibrils, 

 hence not conductile; and the subpellicular system, the last of 

 which is that part of the neuromotor system that concerns with 

 the body ciHa. ten Kate (1927) suggested that sensomotor ap- 

 paratus is a better term than the neuromotor apparatus. 



Protective or supportive organellae 



The external structures as found among various Protozoa 

 which serve for body protection have already been considered 



