156 



General Biology 



adoral ciliated spiral, the rest of the body is without cilia, except in a 

 few species where a circlet of cilia occurs near the aboral end. 



Examples : Vorticella, Carchesium, Zoothamnium. (Fig. 79.) 

 The common members of this order are bell-shaped and attached by 

 a contractile stalk. Certain species are solitary (Vorticella), others 

 form tree-like colonies (Carchesium), and still others are colonial but 



Fig. 77. 



A. Spirostotnum teres (Conn). 



B. Bursaria truncatella (Conn). 



C. Condylostoma patens. (Cal- 

 kins.) 



(From Pratt's "Manual" by per- 

 mission of A. C. McClurg & Co.) 



Fig. 78. 



A. Oxytricha bit aria (Conn). 



B. Stylonychia tnytilus (Dof- 

 lein). 



(From Pratt's "Manual" by 

 permission of A. C. McClurg & 

 Co.) 



with an enveloping mass of jelly (Zoothamnium). The stalk contains 

 a winding fiber composed of myoneme fibrils ; this fiber, on contracting, 

 draws the stalk into a shape like a coil spring. 



34. Subclass 2. Suctoria ( ) Infusoria without 



cilia in the adult stage. No locomotor organs are present, and the 

 animals are attached either directly or by a stalk. An oral groove or 

 mouth does not occur, but a number of tube-like tentacles extend out 

 through the cuticle. 



Examples: Podophyra, Sphaerophyra. (Fig. 80.) 



Ciliates are captured by the tentacles and the substance of the 



