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THE AMERICAN NATURALIST [Vol. LIT 



more common condition— by means of two long, fine, 

 equal, anterior, rapidly vibrating flagella. In the free- 

 swimming stage the posterior pedicel is usually absent, 

 though occasionally individuals may be seen trailing 

 after them pedicels of different lengths. These may be 

 pedicels in various stages of retraction into the body. 



A. globosa (Fig. 12) seems to be of rather rare occur- 

 rence in the waters of ponds and ditches among decaying 

 aquatics. 



Genus Hexamita Dujardin. 



Body very changeable in form, with two long, filamen- 

 tous appendages arising from near the posterior extrem- 

 ity of the body. Flagella four, anterior, active. 



E. inflata (Fig. 13) was found in water containing 

 Ceratophyllum just beginning to decay. 



ORDER EUGLEXIDA 



Genus Ckyptoglena Ehrenberg. 



Body oval, not changeable in form, nor varying greatly 

 among the members of the species; possessing one 

 greenish yellow, or greenish brown chromatophore, or 

 two. Flagellum stout at its base, there may be present 

 a red stigma. Swims rapidly, with an undulatory 

 course. 



Two species, C. conica (Fig. 14) and C. pigra (Fig. 15), 

 seem to be quite common in pond waters among such 

 smaller aquatics as Lemna, Elodea, etc. They are often 

 found in water in which there is decaying vegetation, 

 also, associated with Euglena and Phacus. 



Genus Notosolenus Stokes. 



Body hollowed, resembling the bowl of a blunt, thick, 

 wooden spoon ; hyaline, colorless, and filled with a large 

 number of large, globular, glassy granules or vacuoles. 

 We have observed but very few individuals which did not 

 contain these. Flagellum long, stiff, and stout, and rigid 

 except that its distal fourth only is motile. This pecu- 



