122 PROCEEDINGS OF THE ACADEMY OF 



Hyla leucophyllata, Beireis ; vars. tyjHca et triangulum, Gthr. 



Nauta. 

 Osteocephalus planiceps, sp. nov. 



A rather slender species, "with long limbs, and the general pro- 

 portions of the species of Hyjjsiboas. Head broad and plane on 

 the upper surface to the straight and rectangular canthus rostralis. 

 Loreal region nearlj' vertical. The fronto-parietal bones are ossi- 

 fied, and the nasals meet on the middle line ; their superior surface 

 is rugose with ossific deposit, which in some cases assumes the 

 form of radiating ridges, but nowhere penetrates the free derm. 

 The lateral margins of the fronto-parietals are indicated by deli- 

 cate angular ridges incurred posteriori}-. The vomerine teeth 

 form two curved transverse series between the posterior portions 

 of the inner nares, the angle forwards the outer limb a little longer. 

 Choanffi very large, ostia pharyngea half the size. Tongue oval, 

 bound behind. Eye large with transparent palpebra, its diameter 

 equal to the space between it and the nostril, one-fourth greater 

 than that of the large membranum t^'mpani, and one-fourth less 

 than the frontal width. Belly and sides coarsely areolate, back 

 minutely tubercular. A short tubercular fold from orbit to behind 

 scapula. Fingers free ; toes webbed to the base of the penul- 

 timate phalange of the fourth digit ; first (least) toe webbed to 

 disk. The heel of the extended hind limb extends beyond the ^ 

 muzzle by the diameter of the tympanum. No dermal fringes or 

 processes. 



Color above uniform dark brown, concealed surfaces of limbs 

 similar and without any markings. Sides a little varied with the 

 white of the belt. A light border to the upper lip, and lighter 

 line from the orbit to the angle of the mouth ; dermal scapular 

 fold pale edged. Femur and tibia with dark crossbands on the 

 exposed surfaces. 



M. 



Length of head and body 060 



" " (axial) to angle of mandible . . . .017 



Width " at " " ... .019 



Length of muzzle from orbit 009 



" of fore limb 037 



" of hand 016 



" of hind limb 093 



" of foot 037 



" of tarsus 019 



