GENERAL ZOOLOGY 



Flagellum 



Chloroplast 



Paramylum 

 bodies 



Fig. 8.9. Eugtena viridis: general structure. 

 (Adapted from W. Balamuth in F. A. Brown, 

 Jr., et ai.. Selected Invertebrate Types, copyright 

 1950 by John Wiley and Sons, Inc., printed 

 bv permission.) 



sheath. In Euglena the cavity from which the flagellum extends does not 

 function as a mouth and gullet, for 'in its nutrition the euglena is holophytic, 

 like the green plants. In related flagellates which ingest and digest food, the 

 anterior opening may more properly be called a mouth. In the euglena, in 

 the anterior end of the cell, minute vacuoles periodically enlarge and coalesce 

 to form a contractile vacuole, which discharges into the "gullet." As in the 



Fig. 8.10. A, euglenoid movement; note the extreme plasticity of the cytosome. B, binary 

 fission in Euglena viridis; the division of the nucleus {.M) involves a mitotic process. {A, 



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