THE PROTOZOA 



155 



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 



A. 



Fig. 11. 



A. Spirostomum teres (Conn). 



B. Bursaria truncateUa (Conn). 



C. Condylostoma patens. (Cal- 

 kins.) 



(From Pratt's "Manual" by per- 

 mission of A. C. McClurg & Co.) 



B. 



Fig. 78. 



\. Oxytricha bifaria (Conn). 



J5. Stylonychia mytilus (Dof- 

 lein). 



(From Pratt'a "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 ani- 

 mals are attached either directly or by a stalk. No oral groove nor 

 mouth occurs, but a number of tube-like tentacles extend out through 

 the cuticle. 



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



Ciliates are captured by their tentacles and the substance of the 



