220 



Charles F. Ehret 



onterior 



micronuc 



mocronucleus 



TRICHOCYST— 



CILIUM 



l^Gullet 

 System 



?^^» 



"^-'MITOCHONDRION- '^^ix^^Jj^'iW^^h 



posterior 



anterior 



B. 



posterior 



Fig. 1 . Systems and complexes of organelles in Paramecium. 

 Approximate dimensions: Cilium diameter = 0.25 // 



Cilium tubule diameter = 22-30 m/n 

 Mitochondrion tubule diameter = 34-40 m/i 

 Mitochondrion tubule-lumen diameter = 8-29 m/t 

 Cilium to cilium distance (on centers): 



in gullet system = 0.5 /* 

 in pellicle system = 1.8 /^ 

 length of gullet = 20 /x 

 A. Orientation sketch, and diagram of some hypothetical 



derivatives of primary organelles. 

 B. Patterns of organelle packing at the free cell border. 



1 . Gullet (food-intake) system consists of three organelle complexes: ciliated 

 peniculus (P), ciliated quadrulus (Q) and non-ciliated ribbed-wall (RW); close 

 packed basal 'granule'-tracts are diagrammed. 



2. Surface view of hexagonal complex of pellicle system. Ciliary loci are 

 represented by circles, trichocyst loci by X's; kinetics are formed to the right of 

 the ciliary bases by overlapping kinetodesmal fibrils. 



3. Schematized longitudinal section through pellicle system, along a single 

 kinety; the outer elements are represented as close-packed spheres bearing cilia; 

 the inner elements are 'coralled' out of normal packing-positions (with rare 

 exceptions, viz. at the intersection, on 2, left center) by kinetodesmal fibrils. 

 These inner elements are the trichocysts. 



4. Cross-section of single corpuscular organelle of the hexagonal complex. 

 Four overlapping kinetodesmal fibrils are shown under the right arrow. 



