^^^ Ciliophora 



Fig. 7. 20. A-G. Changes in form observed in Tetrahymena {Letico- 

 phrys) patula (Ehrbg.) Corliss: mature macrostome (A); reproduction in 

 cyst (B); excysted microstome (C); growth of mouth (D, E); young macro- 

 stome with ingested ciliate (F); larger macrostome (G); x325 approx. 

 (after Corliss). H, I. Ciliary patterns in Glaucoma scintillans and Tetra- 

 hymena pyriformh; x540 approx. (after Corliss). J, K. Paraglaucoma 

 rostrata Kahl (?), slender non-feeding stage ("theronte") and larger feeding 

 stage ("trophonte"), x500 approx. (after Mugard). L. Colpidium-lype of 

 ciliary pattern, x540 approx. (after Corliss). 



branes of the posterior daughter are derived from a field of basal granules 

 which originate by multiplication of granules in one or more stomatog- 

 enous rows (Figs. 2. 4, G, H; 7. 19, H). 



Certain species exhibit two morphological phases, the macrostome and 

 the microstome (Fig. 7. 20, A-G). The former, equipped with a large oral 

 pouch, is carnivorous. Both T. patula and T. vorax appear to be dimor- 

 phic in this sense. 



The Family Tetrahymenidae is particularly important because several 

 species — including Tetrahymena patula (Ehrbg.) Corliss, T. pyrijorinis 

 (Ehrbg.) Lwoff and T. vorax (Kidder, Lilly, and Claff) Kidder — have been 

 established in bacteria-free cultures and are being used in physiological 



