AMERICAN FROGS OF THE GENUS RANA. 475 



zygomatic process of squamosal larger than the posterior; terminal 

 phalanges feebly expanded at the end. 



Tadpole large and very similar to that of R. catesbiana in form and 

 general appearance, but mouth larger with the series of horny teeth 

 more numerous, viz. 3 short series on each side behind the long mar- 

 ginal upper series and 4 lower series, the innermost narrowly inter- 

 rupted in the middle; beak narrowly edged with black. 



Habitat. — Central and South America, from southern Mexico to 

 Pernambuco and Peru. 



This frog is interesting as the only representative of the genus Rana 

 in South America. Few species have been more misunderstood and 

 have given rise to more discussion than this R. pahnipes, originally 

 described from the Amazonian region of Brazil. 



It has been made the type of a distinct genus (Ranula, Pohlia) by 

 Peters and by Steindachner, and even referred to the Hylidfe by 

 Giinther (1867). Peters founded the genus Ramda on the feeble 

 dentition: "Die Zahne des Oberkiefers sind so schwach und wenig 

 zahlreich dass man sie erst bei genauer Untersuchung findet und am 

 Gaumen fehlen sie ganz." The explanation is that Ranula gollmeri 

 was described from a recently transformed young, from Caracas, 

 measuring 50 mm. from snout to vent; of this I feel sure, having 

 examined voung from Pebas of exactlv the same size with a short tail 

 and toothless upper jaw. A second, larger specimen, also from Cara- 

 cas, was described at the same time by Peters as Rana affinis, and 

 regarded as so closely related to R. temporaria that it should perhaps 

 rank as a local variety only. A little later, however, Peters recognized 

 that the two supposed species were identical and correctly referred 

 them to R. palmipes. In 1866, Cope took up the genus Ranula and 

 defined it as the American representative of Hyhrana, differing in the 

 "important particulars of the incompleteness of the ethmoid arch, 

 its superior plate being represented by cartilage." Cope, who main- 

 tained the definition up to the close of his labors, can only have 

 examined young specimens, for in the adult the ethmoid is ossified 

 exactly as in Rana temporaria. 



Schlegel, Tschudi, and Dumeril and Bibron referred R. palmipes to 

 the s\Tionymy of R. esculenta; Peters described another specimen as a 

 variety of R. clamitans; Brocchi's R. vaillanti was described as allied 

 to R. mugiens; whilst Giinther (1900), overlooking the small terminal 

 discs of the toes, compared his R. honaccana to R. clamitans and R. 

 drayiojiii. 



