28 



PHYSIOLOGY OF THE INVERTEBRATA. 



vacuole, where the food^is retained until digested. There is 

 no contractile vacuole. 



The Infusoria tcntaculifcra, or Acinetcv (Fig. 3, b), are 

 organisms that move about very little — some of them being 



Fig. 3. — TvrES of Infusoria. 



Representing the Flagellata, the Tentaculifera, and the Ciliata. 



A — Noctiluca. B.= Acineta. C i = Vorticella. C 2 and 3 = Paramoecium. 

 Gv — Gastric vacuole. F = Flagellum. / = Tentacles, n = Nucleus. 

 V = Contractile vacuole, f/i = Mouth. = Oesophagus. 



fixed to a pedicle their whole life. These organisms possess 

 tentacula, or suckers, and are entirely different from the 

 radiating pseudopodia of the Radiolaria. Each tentaculum 

 is a tube (containing a granular fluid) which terminates 



