384 



THE INHABITANTS OF THE SEA. 



greSsion through the water and for drawing alimentary particles 

 int,o-the interior of their body. Though most of the Infusoria 

 live in ponds, morasses,, pools, wells, or cisterns, yet many are 

 marine, as, for instance, the Oarchesium polypinum, which is 

 frequently found attached to corallines, and the Vaginicola 

 valvata, which from its sheath and valve strongly reminds one 

 of a tubicolar annelide. 



Marine Infusoria. 



a. Vapmcola valvata, showing animal extended, and valve ($) raised. 



a'. The same, showing animal contracted within its sheath, and valve ($') shut c 



6. Lagotia viridis, showing rotatory organ (g). b'. Young animal of preceding. 



The wide diffusion both in time and space of the marine 

 Protozoa, and chiefly of the Foraminifera and Polycystina, is t 

 a sufficient proof of their vast importance in the household of 

 the seas. Along with the Diatoms and other microscopical 

 forms of vegetation on which their own existence depends, they 

 evidently constitute the basis on which the superstructure of all 

 the higher orders of the animal life of the ocean reposes. 

 Hosts of minute crustaceans, annelides, acalephse, and molluscs, 

 feed upon their inexhaustible legions, and serve in their turn to 

 sustain creatures of a larger and still larger size until finally 

 Man is enabled to feast on the abundance of the seas. 



