604 



PROTOZOOLOGY 



Fig. 273. a, Oxytricha fallax, X230 (Stein); b, 0. bifaria, X180 

 (Stokes); c, 0. ludibunda, X400 (Stokes); d, 0. setigera, X870 (Stokes) 

 e, T achy soma parvistyla, x490 (Stokes); f, Urosoma caudata, X250 

 (Stokes); g, Aniphisiella thiophaga, X380 (Kahl); h, Eschaneustyla 

 brachytona, X240 (Stokes); i, Gonostomum strenuum, X160 (Engel- 

 mann); j, Hemicyclostyla sphagni, XlOO (Stokes); k, 1, Cladotricha 

 koltzowiiik, X170;1, x300) (Kahl). 



0. setigera S. (Fig. 273, d). Elongate ellipsoid; 5 frontals; 

 ventrals shifted anteriorly; 50)Lt long; fresh water. 



Genus Tachysoma Stokes {Actinotricha Cohn). Flexible; 

 frontals 8-10, of which anterior three are usually the largest; 

 5 ventrals scattered; 5 anals; marginals at some distance from 

 lateral borders, interrupted posteriorly ; fresh or salt water. 



T. parvistyla S. (Fig. 273, e). 10 frontals scattered; about 63/x 

 long; in shallow freshwater pools. 



Genus Urosoma Kowalewski. Similar to Oxytricha; but pos- 

 terior portion drawn out and much narrowed; fresh water. 



