EUGLENA 



(Materials: filter paper, aqueous iodine) 



Classification: Phylum Protozoa, Class Flagellata, Order 

 Autoflagellata. 



Make out: (i) Shape. Is it constant? Compare locomo- 

 tion with that of Amoeba and Paramecium. (2) Flagellum, 

 attachment? Function? A drop of aqueous iodine applied be- 

 fore the coverglass is put in place stains the flagellum on many 

 specimens so it may be seen readily. Since the iodine kills the 

 Euglena a new preparation must be secured for the remainder of 

 the study. (3) Mouth and gullet. Relations to flagellum? (4) 

 Ectoplasm and endoplasm. (5) Red eyespot. (6) Reservoir 

 of the contractile vacuoles. (7) Green bodies, the chromato- 

 phores, containing chlorophyll. (8) The nucleus, near the mid- 

 dle of the body. (9) Occasionally small rounded masses, the 

 paramylum bodies, are found. These are a form of stored ani- 

 mal starch and resemble starch grains. 



Make a drawing, 120 mm. long, showing the parts you have 

 seen. 



With an ocular micrometer find length and width of a 

 Euglena. 



Though the Euglena possesses a mouth and gullet no one 

 has ever 'seen it take solid food particles. In its metabolism it is 

 distinctly plant like. Through the energy of sunlight the chloro- 

 phyll bodies combine carbon-dioxide and water to form starch 

 which is used as food. 



Euglena reproduces by longitudinal fission which begins at 

 the anterior end. The old flagellum is retained by one half while 

 the other half produces a new one. 



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