302 U.S. NATIONAL MUSEUM BULLETIN 2 88 



tiny flecks of a similar nature were present along the shank although 

 these have faded somewhat in preservative. 



Remarks. — Although no additional material has been taken in 

 Colombia since the type series was collected, Bokermann has taken 

 some specimens in Acre, Brazil, and was kind enough to send us one 

 for examination. The only noteworthy variation we have seen in 

 specimens is in the supraocular marks. Sometimes these are discrete 

 spots, one on top of each eye, and sometimes they are fused in the 

 midline to form an interocular bar. 



Specimens Examined 

 COLOMBIA 



Amazon as: Leticia, UF 8501 (holotype), 8502 (paratype). 

 BRAZIL: Acre, WCAB 1414. 



Hyla membranacea Andersson 



Plate 37d-f 



1945. Hyla membranacea Andersson, p. 77 (type locality, Ecuador, Rio Pastaza). — 

 Lutz and Kloss, 1952, p. 651. — Goin and Layne, 1958, p. 106. — Gorham, 

 1963, p. 22. 



Diagnosis. — A member of the leucophyllata group characterized by 

 a uniform brown dorsum and a dark loreal and postocular band that 

 progressively diminishes along the side as it approaches the groin. 



Hyla membranacea is perhaps most similar to H. oliveae, from which 

 it differs in lacking gold spots on the back and in having dark loreal 

 regions, a dark postocular stripe, a more triangular head, and a 

 different voice. 



Description. — UF 8523, from Leticia, Amazonas, Colombia. Vomer- 

 ine teeth in two short, rounded series, lying close together between 

 the small, rounded choanae; tongue one-half as wide as mouth opening, 

 broadly cordiform, its posterior border free and with a trace of notch. 

 Snout short, very broadly triangular when viewed from above, slightly 

 rounded in profile, the upper jaw extending slightly beyond lower; 

 nostrils more lateral than superior, slightly projecting, their distance 

 from end of snout about one-half that from eye, separated from each 

 other by an interval equal to about their distance from eye. Canthus 

 rostralis slightly defined; loreal region nearly flat and very nearly 

 vertical, the upper lip not flaring out strongly below it. Eye relatively 

 large for a frog this size, its diameter slightly exceeding its distance 

 from nostril; palpebral membrane not reticulate; interorbital distance 

 about equal width of upper eyelid, which is relatively wide and slightly 

 greater than distance between nostrils. Tympanum very distinct, 

 about one-third the diameter of eye, separated from eye by a distance 

 nearly equal to its own diameter. Fingers webbed, the web on third 

 finger reaching base of penultimate phalanx; fourth finger but slightly 



