338 HANDBOOK OF PROTOZOOLOGY 



Cepedia cantahrigensis Metcalf (Fig. 145, c). In Rana 

 cantahrigensis. Length 350 microns, width 84 microns. 



Genus Opalina Purkinje and Valentin. Body highly flat- 

 tened. Multinucleate. In amphibians. Numerous species. 



Opalina hylaxena Metcalf (Fig. 145, d). In Hyla versicolor. 

 Larger individuals measure about 420 microns in length, 125 

 microns in width, and 28 microns in thickness. 



Opalina ohtrigonoidea Metcalf (Fig. 145, e-rri). Length 400 

 to 840 microns, breadth 175 to 180 microns, thickness 20 to 25 

 microns. In various species of frogs and toads (Rana, Hyla, 

 Bufo, Gastrophryne, etc.). 



References 



Calkins, G. N. 1926 The biology of the Protozoa. Phila- 

 delphia. 



DoFLEiN, F. AND E. Reichenow. 1929 Lehrbuch der Pro- 

 tozoenkunde. Jena. 



Kent, W. S. 1880 to 1882 A manual of Infusoria. 



Metcalf, M. M. 1923 The opalinid ciliate infusorians. 

 Smithsonian Inst., U. S. Nat. Museum, Bull., No. 120. 



Stein, F. 1867 Der Organismus der Infusionsthiere. Vol. 2. 



Stokes, A. C. 1888 A preliminary contribution toward a 

 history of the fresh-water Infusoria of the United States. 

 Jour. Trenton Natural Hist. Soc, Vol. 1. 



