150 U.S. NATIONAL MUSEUM BULLETIN 2 88 



of disk of third which covers nearly twice the tympanic area; no 

 projecting rudiment of a prepollex; an ulnar fold runs from elbow 

 along outer margin of forearm and hand to tip of fourth finger. Toes 

 fully webbed, the web on fourth toe reaching nearly to base of disk, web 

 on all other toes reaching to disk, third and fifth toes subequal, disk of 

 fourth toe covering half again the tympanic area; first toe shorter 

 than second, not opposable, a distinct oval inner but no apparent 

 outer metatarsal tubercle; a well-developed tarsal ridge extending 

 from tip of fifth toe along outer margin of foot to heel; no dermal 

 appendage on heel. Body elongate, in postaxillary region a little 

 narrower than greatest width of head; when hind leg is adpressed, 

 heel reaches to tip of snout; when limbs are laid along the side, knee 

 and elbow overlap; when hind legs are bent at right angles to body, 

 heels overlap considerably. No patagium. Skin of upper parts very 

 finely glandular; a moderately heavy glandular fold (parotoid) hangs 

 behind the tympanum and angle of jaw to about the level of lower 

 margin of jaw; a pair of slightly projecting, rounded, glandular areas 

 just above the vent, but these not projecting out as a conspicuous 

 ridge or appendage; skin of throat and chest smooth, that of belly 

 and lower femur uniformly granular; no apparent traces of a skin- 

 fold across chest; no apparent vocal sac. Skin of head not co-ossified 

 with skull, roof of skull not exostosed. 



Dimensions. — Head and body, 92.8 mm.; head length, 28.2 mm.; 

 head width, 29.3 mm.; femur, 43.3 mm.; tibia, 48 mm.; foot, 63.2 mm.; 

 hand, 27.4 mm. 



Color in alcohol. — A rather somber colored frog for an Agalychnis, 

 now a pale bluish above and pale yellowish below with no sharp line 

 of demarcation between dorsal and ventral colors. The dorsal color 

 is over the entire dorsal surface of head and body, in a narrow line 

 margining the lower lip, a line on the upper surface of forearm and 

 fourth finger, a trace of pigment on third finger, a narrow stripe along 

 the dorsal surface of thigh, a stripe along the margin of dorsal surface 

 of metatarsal region and on dorsal surface of fourth and fifth toes 

 (except on tip of fourth toe). The tarsal and ulnar folds are whitish, 

 and there are three very brilliant, clear white, black-encircled spots 

 on the back. The palpebral membrane is reticulated. 



Variation. — The four specimens in the type series comprise two 

 adult females, an adult male, and a juvenile. The male differs in having 

 a well-developed, brown, horny pad on the underside of the thumb 

 and seems in general to be slightly more slender in build than are the 

 two adult females. The immature specimen (27.8 mm.) has faded to 

 a lavender rather than a pale blue color, but it is patterned like the 

 adults. 



The series of eight fresh specimens (CJG 2433-40) from the Rio 



