GENERAL ZOOLOGY 



Fig. 8.25. Representative Suctoria, mature and immature stages. A, Aanela; B, Podophrya, 

 feeding on small ciliates; C, ciliated juvenile stage of Podop/irya; Z), similar stage oi 7 oko- 

 phrya. {A, adapted from W. S. Kent, 1880, Manual of the Infusoria; C and D, adapted, after 

 A. Kahl, from R. P. Hall, Protozoology, copyright 1953 by Prentice-Hall, Inc., printed by 

 permission.) 



Order Oligotrichida — cilia greatly reduced in numbers and specialized; mostly 

 parasitic and known principally from the digestive tracts of herbivorous 

 mammals, but some free-living representatives. Diplodimum, Halteria, 

 Strornhidium, etc. 



Order Hypotrichida — cilia scattered and highly specialized for locomotion 

 and feeding; some as sensory organelles. Cell usually flattened and with 

 what may be termed dorsal and ventral surfaces; typically creeping 

 forms. Euploles, Slylonychia, etc. 



Order Peritrichida — cilia usually restricted to a conspicuous di.sc-like oral 

 region and a basal region at opposite end; more familiar forms attached 

 to substrate by a contractile stalk. Carchesium, Epislylis, Trichodma, 

 Vorhcella, 7oothammum, etc. 



The Suctoria 



The class Suctoria comprises a small group of Protozoa placed in the sub- 

 phylum Ciliophora because cilia are present during the immature, motile 



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