FROGS OF COLOMBIA — COCHRAN AND GOIN 87 



of penultimate phalanx of third; digital tips not expanded; no pro- 

 jecting rudiment of a pollex; no ulnar ridge. Toes slightly webbed 

 at base; the web on fourth toe reaching the base of the antepenultimate 

 phalanx, third toe much longer than fifth; metatarsal tubercles not 

 present; no tarsal ridge; no dermal appendage on heel. Body rather 

 elongate, in postaxillary region slightly broader than greatest width 

 of head; when hind leg is adpressed, heel reaches axillary region; 

 when limbs are laid along the side, knee and elbow fail to meet; 

 when hind legs are bent at right angles to body, heels fail to meet 

 by internarial distance. Skin of upper parts smooth. A narrow dorso- 

 lateral fold passes from above the tympanum to the region of the 

 groin on each side. A rather narrow glandular ridge encircles upper 

 part of tympanum. Skin of throat, chest, and belly smooth; no 

 trace of a skinfold across chest; adult female, no vocal sac. Abdomen 

 packed with large, unpigmented eggs. 



Dimensions. — Head and body 51.7 mm.; head length 17 mm.; head 

 width, 18.3 mm.; femur, 19.1 mm.; tibia, 11.8 mm.; heel-to-toe, 25 

 mm.; hand, 11.5 mm. 



Color in alcohol. — Dorsum uniform dark brown medially. A pale, 

 narrow, cream-colored stripe extends from eye to eye around the tip of 

 snout, passing just above the nostrils. This stripe widens appreciably 

 just behind each eye and passes posteriorly on each side above the 

 tympanum in the form of a broad, cream-colored dorsolateral stripe 

 all the way to the groin, where it again narrows and passes along the 

 anterior faces of the thigh and shank as a narrow cream-colored stripe. 

 Posterior side of thigh dark with light mottlings arranged more or less 

 in the form of a stripe. Lower surfaces somewhat paler than dorsum, 

 darkest under the chin and throat, becoming paler posteriorly. Indis- 

 tinct but discrete, rounded, scattered, brown ocelli-like dots on the 

 chin, throat, and chest. 



Remarks. — This very distinctive genus is still, to the best of our 

 knowledge, known from only four specimens — the type; a specimen in 

 the American Museum (AMNH 1325) which has no data other than 

 that it was obtained from the museum in Georgetown, British Guiana; 

 a specimen in the University of Michigan collection (MZUM 85137) 

 from Arabop6, Venezuela; and the specimen, described above, from 

 the lower Rio Apaporis in Colombia. 



This is surely the most distinctive microhylid in South America. 

 The large, conspicuous tympanum and the very flat-topped head set it 

 off at a glance from all others. 



The specimen at hand, a gravid female, has the abdomen packed 

 with large, unpigmented eggs, a condition usually associated with 

 terrestrial breeding habits. 



We have not examined the type of this species, but from available 



