THE OPALIISriD CILIATE INFUSORIANS. 349 



Rana draytonii {0. draytonii, [Z]) ; Pacific coast of the United 

 States. 



Rana erythraea (O. rotunda, [Z]) ; Siamese Cambodia. 



Bana esculenta {O. ranarum, [Z]); Switzerland. 



Rana japonica {O. japonica, [Z]) ; Japan. 



Rana limnocharis {O. japonica, ?, [Z]) ; Java. 



Rana limnocharis (O. lata, [Z]) ; "Asia." 



Rana mascareniensis {O. sp. ?, [Z]) ; Gold Coast. Africa. 



Rana palustris {O. oltrigonoidea, [A']) ; Ohio, Massachusetts. 



Rana pipiens (0. ohtHgonoidea, [A']); North Carolina. Ohio, 

 Illinois. 



Rana pipiens austricola {0. ohtrigonoidea austricola. [^4]); 

 Costa Rica ; Guatemala ; Tabasco, Mexico. 



Rana pipiens sphenocephala {0. caroliTiensis, \_A'\) ; Florida, 

 South Carolina. 



Rana pretiosa {O. copei. [Z ?]) ; Montana. 



Rana septentrionalis {Op. sp. ? [^]); Ontario. 



Rana sylvatica (O. virguloidea, [^]) ; Ohio, North Carolina. 



Rana temporaria {0. ranarum, [Z]) ; Europe, Japan. 



Rana temporaria (0. ranarum form cinctoidea, [Z]) ; Germany. 



Rana temporaria {O. ranarum form truncata, [Z]) ; Germany. 



Rana temporaria parvipalnnata {0. ranarum parvipolmatae, 

 [Z] ) ; France. 

 The species of the genus Opalina show two divergent groups' 

 Opalinae angustae, forms which are long and narrow, especially 

 behind, like O. ohtrigona; and Opalinae latae, which are broad like 

 0. ranarum or O. cincta. The Opalinae angustae may be vaguely 

 divided into the curved, virgula-Wk^ species and the straighter, 

 ohtrigona-hke species, but this distinction is vague and of little 

 interest. The Opalinae angustae, with two exceptions, are Western 

 Hemisphere forms, the Ophalinae latae, with possibly from three to 

 five exceptions, are found in the Eastern Hemisphere. One Dis- 

 coglossid is reported to harbor an Opalina {ranarum), a very rare 

 occurrence, of which there is but a single report. It may not have 

 been a permanent infection. In the Pelobatidae the only Opalinas 

 known (3 species) are of the narrow group. In the Hylidae the 

 ohtrigona-Wko, froms predominate, though there arc five Opalinas 

 of the virguloid form. All these, of course, are narrow, though in 

 three of the ohtrigona-Wke, species some broad individuals, almost 

 ranarum-like, are seen along with the slenderer -individuals. The 

 Bufonidae show about equal numbers of the narrow and the broad 

 Opalinids. From one species of the Gastrophrynidae, the only one 

 known to be infected with Opalina, we have a single species of 

 oltrigona-Yi^Q Opalina. No Opalinae are known from the Den- 

 drohatinae. They are very numerous among the Raninae; a few are 



