Cochran and Goin (1970) were unaware of the identities of _Hyla verrucigera_ and _riopastazae_; they used the later name _Osteocephalus orcesi_ for Colombian frogs that are correctly referred to _O. verrucigerus_. Although Goin (1961) placed _Hyla buckleyi_ and _H. pearsoni_ in _Osteocephalus_, Cochran and Goin (1970) recognized a "_buckleyi_ group" in _Hyla_ that included these two species plus a new species, _Hyla cabrerai_ from Amazonian Colombia and Brasil (total of three specimens). Also, these authors named _Hyla carri_ from a single Colombian specimen. Study of the types of _Hyla cabrerai_, _H. carri_, and _H. festae_ Peracca, 1904, from Ecuador, reveal that all of these names are synonyms of _Osteocephalus buckleyi_. Much of the taxonomic confusion and multiplicity of trivial names is due to the great amount of color variation in _taurinus_ and to the sexual dimorphism in the texture of the dorsal skin in all of the species. The details of variation in these and other characters and our justifications for the synonymies are given in the accounts of the species. All of the trivial names that apply to species herein recognized as members of the genus _Osteocephalus_ are listed in table 1. =Osteocephalus= Steindachner, 1862 _Osteocephalus_ Steindachner, 1862:77 [Type species.--_Osteocephalus taurinus_ Steindachner, 1862, by original designation]. Not _Osteocephalus_ Fitzinger, 1843:50 (_nomen nudum_). _Diagnostic Definition._--1) Skull broader than long; 2) dermal roofing bones of skull well ossified, exostosed, and/or co-ossified in some species; 3) prenasal and internasal bones absent; 4) parasphenoid alae posterolaterally oriented; 5) dentigerous processes of prevomers angular (/--\); 6) vocal sacs paired, posterior, and when inflated protruding posteroventral or posterolateral to angles of jaws; 7) submentalis muscle moderate in size and araphic; 8) intermandibularis muscle undifferentiated and bearing an elongate median aponeurosis; 9) parotoid glands absent or poorly developed, skin not producing viscous secretion characteristic of _Phrynohyas_; 10) skin on dorsum tuberculate in males, smooth in females; 11) tympanum large, 60 percent or more of diameter of eye; 12) fingers about one-third, toes more than three-fourths webbed; 13) discs large, round; 14) nuptial excrescences present in breeding males; 15) inner metatarsal tubercle not modified for digging; 16) outer metatarsal tubercle absent; 17) tarsal fold weak or absent; 18) pupil horizontal; 19) palpebrum clear; 20) known tadpoles having two upper and five lower rows of teeth. TABLE 1.--Alphabetical Synonymy of the Species of _Osteocephalus_.