334 



THE BIOLOGY OF STENTOR 



a holdfast at the pointed end, and at the other end a wholly frontal 

 disposition of the feeding organelles, which spiral clockwise as seen 

 from above, and consist most obviously of an almost complete 

 circle of membranelles terminating in a mouth but with no 

 undulating membrane. The implication of variable morphology in 

 the names polymorphus and multiformis is misleading and erroneous. 

 The most complete and recent treatment of the taxonomy of 

 stentors is to be found in the great work of Kahl (1935) on the 

 classification of ciliates. Since his writing, one species has been 



/eti£i 



-pohfTnOt-phuS 



roeseli 



mzijelLeri 



pi/gmseus 



Fig. 95. Species of Stentor. The coerideus is about 500 /x in 

 length and others are approximately in scale. S. pygmceiis after 

 Swarczewsky, 1929; rubra and loricata after Bary, 1950; felici 

 after Villeneuve-Brachon, 1940; and amethystiniis after Kahl, 

 1935- S. introversus (contracted and expanded; after Tartar, 

 1958a) and others were drawn from life, 



