254 tr. S. NATIONAL MUSEUM BULLETIN 2 06 



species of the genus Cydoramphus found in or within a very short 

 distance of the city of Rio de Janeiro. One, with a smooth skin and 

 toes entirely devoid of webs, was not known to early authors; it was 

 named Iliodiscus eleutherodactylus by Miranda-Ribeiro in 1920. Two 

 others have distinct webs on the toes and skin that may be smooth 

 or granular according to individual variation. Of these, one has a fuller 

 web and much longer legs, the adpressed heel reaching beyond the 

 tip of the snout, its tibia being between 53 and 56 percent of the total 

 length. This seems to be the species designated by Steindachner in 

 1864 as Telmatohius brasiliensis, but at that time already properly 

 bearing the name of Cydoramphus julginosus Tschudi (given as 

 iuliginosus by Dumeril and Bibron in 1841). The last species has a 

 distinctly shorter web on the hind feet, with a considerable part of 

 the fourth toe left free. It has very short legs, the adpressed heel 

 reaching only to between the posterior and anterior corners of the 

 eye, its tibia being 44 to 49 percent of the total length of head and 

 body. This species is considered to be that designated by Cope as 

 Grypiscus umhrinus, which Dr. Lutz (1929a) mentioned and figured 

 as Cydorhamphus fuliginosus and to which Miranda-Ribeiro (1929b) 

 applied the new name of Iliodiscus lutzi. 



Although Miranda-Ribeiro (1935) put his Iliodiscus dubius from 

 Alto da Serra into the synonymy of brasiliensis of Steindachner, dubius 

 appears to belong to the synonymy of Cydoramphus asper Werner. 

 On comparing the numerous frogs from Alto da Serra with the Rio de 

 Ja,neiran examples of fulginosus {= brasiliensis) it may be immedi- 

 ately noted that the former have heavily tubercular skins and that 

 the toes are webbed only at the base, while in fulginosus from Rio de 

 Janeiro the skin is at most slightly granular, and the webs extend 

 nearly to the tips of the toes. The shape of the head and body is very 

 similar in these frogs and without seeing examples from both localities 

 side by side it would be quite easy to confuse them. 



The full range of variation in the several species making up this 

 genus is still only partly known, and additional material from Minas 

 Gerais, Rio de Janeiro, Sao Paulo, and Santa Catarina must be 

 gathered and compared with the existing types before an adequate 

 revision is possible. 



For a statistical analysis of measurements of the species of Cydo- 

 ramphus here discussed, see pages 373 and 381, 



Key to the species of Cydoramphus of southeastern Brazil 



a>. Spines on thumb ohausi (p. 264) 



a*. No spines on thumb. 

 ¥. Hind feet webbed. 



c». Toes more than two-thirds webbed. 



