I 



THE OPALINID CILIATE INFUSORIANS. 429 



of the American Hyla versicolor seem to be infected in less propor- 

 tion than are the tadpoles. Neresheimer's belief that all healthy frogs 

 bear Opalinids is not borne out by a review of even our scanty data 

 from living Anura. It is probably not true of any species of Anura. 

 Second. — The inquiry as to Anura which may be infected by more 

 than one species of Opalinid is answered, so far as our data is con- 

 cerned, by a glance at the following list. 



Family DISCOGLOSSIDAE. 



Bombinu boinbina: Protoopalina caudata, P. intestinalis, and Opalina ranarum 



(very rare). 

 B. orientalis: Proloopalina macrocaudata and P. orientalis. 

 B. pachypa: Protoopalina caudata and P. intestinalis. 

 Discoglossus pictus: Protoopalina "intestinalis" Opalina ranarum (Brumpt, 



1915). 



Family PELOBATIDAE. 



Scaphiopus hamnwndii: Protoopalina hamnumdii and Opalina oManceolata. 

 S. solitarius: Zelleriella scaphiopodos, Opalina ohlanceolata, 0. obtrigonoidea 

 and Cepedea (?) " flava." 



Family HYLIDAE. 



Hylu bandinii: Cepedea bandinii and Opalina yuatemalae. 



U. pickeringii: Opalina pickeringii and 0. obtrigonoidea. 



II. regilla: Opalina oregonensis and 0. virguloidea. 



II. septentrionalis: Zelleriella [of Hyla septentrionalis] and Opalina species 



unnamed. 

 H. versicolor: Opalina hylaxena and forms orbiculata, parvinucleata and geor- 



giana. 



Family BUFONIDAE. 



B. bufo: Cepedea dimidiata, Opalina ranarum and 0. cincta. 



B. bufo asiaticus: Protoopalina axonucleata, Opalina bufoxena and 0. asiatica. 



B. cognatus: Opalina discophrya and Zelleriella hirsuta. 



B. compactilis : Opalina gigantea and 0. spiralis. 



B. copei: Opalina discophrya and another unidentified but different Opalina. 



B. fowleri: Opalina obtrigonoidea and form rugosa. 



B. haematiticus: Cepedea doliehosnma. 0/K///»rt species (?) and Zelleriella bufo- 

 xena. 



B. lentiginosus: Cepedea obovoidea and Opalina triangulata. 



B. melanostictus: Cepedea formosae. C. pulchra javanensis, Protoopalina for- 

 mosae and a doubtful record of Zelleriella macronucleata. 



B. peltocephalus : Protoopalina bufonis and Z. sp. ?. 



B. punctatus: Zelleriella [of Bufo punctatus] and Opalina obtrigonoidea. 



B. regularis: Protoopalina regularis and P. stevensoni. 



B. typhonius: Zelleriella opisthocarya subspecies (?) and Opalina paiiam- 

 mensis. 



B. viridis: Protoopalina caudata, Cepedea dimidiata and Opalina ranarum. 



B. woodhousi: Zelleriella icoodhousi and Opalina woodhousi. 



