278 U. S. NATIONAL MUSEUM BULLETIN 206 



stripe along the canthus; a triangular, seal-brown, postanal patch 

 sharply outlined anteriorly but fading out below the thighs; lower 

 surface of tarsus between the tarsal ridges seal brown ; ventral surfaces 

 also covered with minute wood-brown dots on the throat and chest, 

 immaculate posteriorly. 



Variations. — The five other examples from Alto da Serra are very 

 close to the described specimen in most details. The disks seem to 

 vary a little in size, being scarcely enlarged on the toes in some cases 

 and distinctl}^ enlarged in others. The tympanum is less visible in 

 the softer specimens, and in these also the dorsolateral folds are not 

 apparent. Two of the frogs show a dark triangular patch under the 

 eye. The general build, limb proportion, and head contour seem 

 remarkably constant, however. The adpressed heel extends to the 

 nostril in four and to the tip of the snout in one individual. The 

 largest specimen, 22 mm. long, comes from Independencia, near 

 Petr6polis, The coloration of all the specimens is very constant. 



Remarks. — Eleutherodactylus -parvus can be told from the young of 

 other eleutherodactyli by the presence of the dark postanal triangular 

 patch, as well as by its wide head and its very short, stout body. It 

 is found in forests on the mountains near the city of Rio de Janeiro, 

 living among the fallen leaves with Leptodactylus marmoratus, 

 Zachaenus parmilus, and E. guentheri. Five very young ones from 

 Tijuca, now bleached but presumably of this species, measure between 

 10 and 12 mm. in length. 



The finger and toe disks of this species vary even more than usual 

 for the genus. The tips may be bluntly rounded, or quite pointed 

 when seen from above. The upper side of each tip may be a single, 

 rounded, pillowlike or flat surface, but sometimes a median division 

 may be apparent in some or most of the disks, so that they closely 

 resemble those of Basanitia lactea. These two species are about the 

 same size, and are superficially similar. Basanitia lactea, however, 

 has a much larger eye in proportion to its snout length, and has only 

 a slight darkening of the postanal region, instead of having a very 

 distinct triangular patch, as in parvus. 



While parvus of southeastern Brazil is quite clearly related to the 

 Mexican E. rhodopis Cope, cotypes of which are in the U. S. National 

 Museum, the former differs in having a prominent narrow dorsolateral 

 ridge from eyelid to groin; in having a smaller eye, a broader inter- 

 orbital width and a shorter snout, and a smaller size, the adult probably 

 not exceeding 22 mm. 



The first of the seven examples listed by Miranda-Ribeiro (1923c, 

 p. 17) as rhodopis (MP 344, Raiz da Serra, Sao Paulo) is practically 

 identical with the Rio de Janeiran topotypes of parvus. Hence it is 

 positive that Miranda-Ribeiro's rhodopis refers only to parvus. 



