EU CI LI AT A, HOLOTRICHIDA 359 



Genus Ophryoglena Ehrenberg. Body elliptical or some- 

 what cylindrical. Ends are equally rounded or attenuated. 

 Cytostome usually crescentic, near the anterior fourth. An 

 undulating membrane. Contractile vacuole one or more and 

 with numberous radiating canals. Macronucleus elongated or 

 band-form; micronucleus fusiform. 



Ophryoglena flava Ehrenberg (Fig. 154, b). Body 500 to 550 

 microns long. Stagnant water. 



Genus Cyrtolophosis Stokes. Body oblong; secretes muci- 

 laginous envelope in which the organism lives, but from which 

 it emerges at will. A tuft of curved vibratile coarse cilia at the 

 anterior end. Cytostome at the end of a short peristome and 

 circular. Long cilia on the peristome. Macronucleus central 

 and spherical. A posterior contractile vacuole. Fresh water. 



Cyrtolophosis mucicola (Fig. 154, c). Body 25 to 30 microns 

 long. In infusion of dead leaves. 



Genus Loxocephalus Eberhard. Body elliptical ; anterior end 

 obliquely truncate and bent to one side. Near this end, one or 

 more short, curved setae on one or both sides. Usually one 

 (sometimes more) long caudal setae at the posterior extremity. 

 The cytostome below the bent anterior portion, indistinct. 

 Macronucleus ovoid, central; one contractile vacuole. Fresh 

 water. 



Loxocephalus granulosus Kent (Fig. 154, d). Body about 

 50 to 60 microns long. In decaying vegetation. 



Genus Uronema Dujardin. Body elongate ovoid. Cyto- 

 stome ventral; oblong with an extensible trap-like membrane. 

 Ciliation uniform. One or more caudal setae at the posterior 

 end. A contractile vacuole posterior. Fresh or salt water. 



Uronema marina Dujardin (Fig. 154, e). Body about 30 to 

 50 microns long. Common in decaying algae. 



Genus Dallasia Stokes. Body elongate-ovate, subcylindrical, 

 produced posteriorly into a more or less retractile tail-like pro- 

 longation. One side convex, the other flattened. Cytostome 

 near the anterior end and roughly triangular with two undu- 

 lating membranes. Nucleus oblong, central. One contractile 

 vacuole. 



Dallasia frontata Stokes (Fig. 154, /). Body 65 to 140 

 microns long. Polymorphic. Fresh water. 



