_Specimens examined._--Six, as follows: BRITISH GUIANA, _Dist. Demarara_: Marudi Creek, AMNH 44749; _Dist. Equibo_: Tumatumari, MCZ 11790 (paratype); _Dist. Rupununi_ (_Berbice_): Wai Wai Country, N of Acarahy Mountains, west of New River (2 deg.N, 58 deg.W), KU 69890. Also, 3 specimens from "probably British Guiana," AMNH 70108-10 (70110 cleared and stained). SYSTEMATIC ACCOUNT The availability of additional material and the new information pertaining to osteology permit an amplification of Gaige's (1926) description. Genus ~Allophryne~ Gaige _Allophryne_ Gaige, Occas. Papers Mus. Zool., Univ. Michigan, 176:1, Oct. 14, 1926. Crawford, Annals Carnegie Mus., 21(1):29, 32, Nov. 14, 1931. Noble, The biology of the amphibia. McGraw-Hill, p. 510, 1931. Ruthven, Herpetologica, 1:3, July 11, 1936. Gallardo, Papeis Avulsos, 17:79, Jan. 1, 1965. _Type species._--_Allophryne ruthveni_ Gaige. _Diagnosis and definition._--A genus of diminutive frogs; vomers, maxillae, and premaxillae edentate; skin of head strongly anchored to connective tissue on cranium; prepollical spine absent in males; disk of third finger larger than tympanum, smaller than eye; no humeral hook in either sex; ilia extending anteriorly beyond sacral expansions; adults attaining snout-vent length of 31 mm.; male having darkened external subgular vocal sac; skin of dorsum pustulate. ~Allophryne ruthveni~ Gaige _Allophryne ruthveni_ Gaige, Occas. Papers Mus. Zool., Univ. Michigan, 176:1-3, pl. I, Oct. 14, 1926. Crawford, Annals Carnegie Mus., 21(1):32, Nov. 14, 1931. Ruthven, Herpetologica, 1:3, July 11, 1936. Barbour and Loveridge, Bull. Mus. Comp. Zool., 96(2):64, Feb., 1946. Peters, Occas. Papers Mus. Zool., Univ. Michigan, 539:10, Sept. 19, 1952. _Holotype._--University of Michigan Museum of Zoology 63419, adult female, from Tukeit Hill, below Kaiteur Falls, Equibo District, British Guiana; obtained in May, 1924, by E. N. Clarke. _Diagnosis._--Fingers free; toes two-thirds webbed; no supernumerary tubercles on soles or palms; no tarsal fold; elongate anal sheath, anal opening on lower surface of thighs; head broad, interorbital space 2.5 times width of upper eyelid; snout subacuminate in dorsal profile, strongly sloping in lateral profile; tympanum visible in males, concealed in females; venter areolate.