THE PHYLUM PROTOZOA 



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nuclei of the offspring. The details of this process will be described 

 later. 



Paramecia. The best known genus of ciliates is Paramecium (Fig. 

 8.12). Several of the species (such as P. caudatum) are large and easily 

 cultured. They present many interesting biological problems and are 

 widely used in experimental work. Paramecia measure from 0.1 to 0.3 

 mm. in length. The body is blunt anteriorly, widest just behind the 

 middle, and tapered posteriorly. They are rapid swimmers, revolving 

 as they move forward in a spiral path. The gullet is located to one side, 



Figure 8.12. Paramecium. Generalized drawing combining features of several species. 



