THE OPALINID CILIATE INFUSORIANS. 339 



Africa from the north at a period after Africa had broken its con- 

 nection with South America (p. 363). The genera Hyperolius and 

 Phrynomantis have not reached tropical America. Apparently no 

 Raninae have entered South America from Africa, but Gastrophry- 

 nidae seem to have come by this route and may have brought Cepedea. 

 Pipa, or rather its ancestor, may have been an immigrant from 

 Africa, for its known relatives are two African genera, Xenopus and 

 Hymenochirus, and Palaeohatraehus^ from mid-Tertiary deposits in 

 central Europe. No Opalinidae are known from Pipa. The an- 

 cestors of the Dendrohatinae of South America probably came from 

 Africa, but neither American nor African members of this sub- 

 family are known now to carry Oepedea^ Bufo^ being absent from 

 Madagascar, probably was not in continental Africa until after 

 Africa lost connection with South America (fig. 235, p. 302). The 

 Gastrophrynidae are, therefore, the most probable hosts for African 

 Cepedeas entering South America. The Cepedeas have been brought 

 to America in hosts which did not belong to the Hylidae which is 

 American and Australian and not Euro-Asian or African. Gepedea 

 dimidiata [paraguensis'\ shows no close similarity to any other 

 American species, or to any known African species, and I do not 

 see that we have any light to help us understand the presence in 

 southern South America of this apparent near relative of the Euro- 

 Asian Cepedeas of this second group. There are no known members 

 of this group in tropical Africa or in North America. Further 

 knowledge of the Gepedea faunas may sometime solve this puzzle 

 for us, but we find no solution in the data now known. 



Division 3. 



C. spinifera in Oxyglossus (Raninae) Java. 



This species, which bears an abrupt, unciliated, spinelike, posterior 

 process, seems not to be very closely related to any other known 

 species of Gepedea^ its posterior spine and long cilia being distinctive, 

 Oxyglossus^ its host, is known from India and the East Indies. A 

 fossil form assigned to this genus is said to occur in the " Eocene " 

 or " Comanchian " of Wyoming.^^ Gepedea spinifera may have arisen 

 in Java in the Pleistocene after Jara became finally isolated. 



Division 4, A (fig. 251, dots). 



C. phrynomantidis (p.l48). in Phrynomantis (Gastro- 



phrjniinae) East Africa. 



C. madagascariensis (p.l49)..in Megalixalus (Raninae). Madagascar. 

 C. madagascariensis [of. Hyperolius] (p. 150). in H3rperolius (Raninae). West- 

 em Tropical Africa. 



C. magna (p. 150) in Biifo Western Tropical Africa. 



C. obovoidea(p. 161) in Bufo Florida. 



s^Gadow (1909), "Eocene"; Schuchort (1915?), "Comanchian," but the identification 

 as Oxyglossus must be regarded as yery doubtful. 



