THE OPALINID CILIATE INFUSORIANS. 441 



gametic nuclei are direct derivatives of the ordinary nuclei, vegeta- 

 tive chromidia being formed previous to sexual reproduction. He 

 says chromidia are formed during only part of the life cycle. These 

 are vegetative chromidia (and possibly also reproductive chromidia, 

 Neresheimer), function unknown. He says Hartmann considers the 

 chromidia vegetative (after Metcalf). Swarzewsky quotes Nere- 

 sheimer's observations of reproductive chromidia and says they can 

 not be accepted without further investigation. 



Andre (1913), notes the occurrence of Opalina ranarum and 

 Cepedea {^^ Opalina^^) dimidiata in both Rana temporarla and R. 

 esculenta [The latter is an unusual host record for 0. ranai^ni], 173 

 out of 233 specimens of R. temporana being infected, the males and 

 females equally so. Opalinids and Flagellates are present in inverse 

 proportions, that is, if the Opalinids are abundant there are few 

 Flaggellates and vice versa. Rana esculenta is chiefly infected with 

 Cepedea dimidiata., though some have Opalina ranaimm. One frog 

 of this species was found bearing Protoopalina (" Opalina ") intesti- 

 nalis. In this frog Cepedea dimidiata lives less readily with the 

 Flagellates. He says 82 to 89 per cent of Ranxi esculenta in different 

 localities are infected with Opalinids. 



Awerinzew (1913) describes the new species Protoopalina {'■'■ Opa- 

 lina ") primordialis from Rana nutti from German East Africa. 

 Awerinzew is quoted in full in the present paper. Section 3, under 

 P. primordialis on page 31. 



Collin (1913) describes the new species Opalina cincta from Bufo 

 hufo (" vulgaris ") . He reports Protoopalina (" Opalina ") " intesti- 

 nalis " from Pelohates culfripes from Montpellier, France. He notes 

 that both Nyototherus and " Opalina'' in the spring infect tadpoles 

 of Anura by means of cysts, a similarity of habit doubtless due to 

 parallel adaptation to similar conditions of parasitism. He reports 

 cysts of Oplinids in tadpoles of Alytes and Bufo calamita. 

 ^ Liihe (1913). I have failed to find in this country the 1913 edition 

 of Lang's Lehrbuch which contains Liihe's discussion. 



Poche (1913) refers to the uniformity of the nuclei in " Opalina.'' 

 He gives a classification, as follows : 



VII Classe, INFUSORIA. 



I Ordnung, Holotricha. 

 I Unterordnung, Opalininea. 

 I Familie, Opalinidae. 

 One genus, only, " Opalina " [including, of course, the four present 

 genera]. Hartog's (1906) and Neresheimers (1907) opinions that 

 Opalinids should be classed among the Flagellata are rejected in 

 S3103— 23 29 



