370 BULLETIN 120, UNITED STATES NATIONAL MUSEUM. 



The Ranidae (figs. 230, 231, p. 294). 



The Ranidae have their nearest relatives probably in the Gastro- 

 phrynidae. The distribution of the two families is very similar 

 (figs. 229, 230, 231), except for the two facts, first, that no Ranids 

 are in the southern half of South America and, second, that the 

 Ranidae have spread throughout Arctogea, being represented in 

 North America and Europe by the genus Rana and in northern Asia 

 by the genera Polypedates and Rana. A fossil form, assigned to the 

 genus Oxyglossus (one of the Raninae), whose present home is in 

 India and the East Indies, is reported from the "Eocene" (Gadow, 

 1909) or "Comanchian" (Schuchert, 1915 ?) of Wyoming, but the 

 identification is of very doubtful validity. Both families are well 

 represented in tropical Asia and Africa. Both are in Papua. Both 

 are in South America. Both Raninae and Bendrobatina^, are in 

 tropical Africa, Madagascar, and tropical America, but the Dendro- 

 hatinae are absent from tropical Asia-Malaysia-Papuasia. Both 

 Ranids and Gastrophrynids are absent from Australia, Tasmania, 

 and New Zealand. Omitting the two northern genera, Rana and 

 Polypedates^ and the Wyoming fossil, the distribution of the two 

 families is seen to be almost identical, the only difference being the 

 presence of a few Ranids in the Malay Islands and their absence 

 from the southern half of South America. Both families seem to 

 have arisen in South Atlantis (Africa-South America) and its Mada- 

 gascar-India extension in early Cretaceous times (fig. 234) and to 

 have entered continental Asia from India during the late Tertiary, 

 spreading during the same period to Malaysia, Japan, and Europe. 



The subfamily Raninae has the same distribution as the family, 

 except that it is not in the Solomon Islands. The South American 

 genera should be more thoroughly searched for Opalinids. Phyllo- 

 hates and ProstJierapis from Venezuela and Columbia bear Zelleri- 

 ella. Phyllodromus^ Calosthetis, and Hylixalus have not been ex- 

 amined. The three poorly preserved specimens of the South Ameri- 

 can Rana palmipes^ which were examined, showed no Opalinids. 



The important genera Polypedates {''^Rhacophorus'''') and Rana 

 deserve further mention. Polypedates occurs in Madagascar, Ceylon, 

 India, Malaysia, including the Philippines, and through eastern Asia 

 into Japan. It seems to have arisen in India or upon the Madagas- 

 car-India ridge and to have passed to continental Asia and into its 

 present localities during the later Tertiary. (Fig. 237.) Its absence 

 from Africa is unexplained and seems in disagreement with the 

 charts upon which our discussion is based, for they show Madagascar 

 united to Africa after the Madagascar-Ceylon-India bridge had been 

 interrupted. 



