18 U.S. NATIONAL MUSEUM BULLETIN 2 88 



of snout; interorbital diameter 1% times that of upper eyelid, greater 

 than interval between nostrils. Tympanum distinct except for its 

 upper posterior edge, its greatest diameter half that of eye, not 

 separated from eye by an appreciable distance. Fingers long, with 

 lateral ridges, free, first finger nearly equal to second, fourth longer 

 than either, its tip reaching to base of penultimate phalanx of 

 third, the disk of which covers about one-eighth the tympanum; a 

 small weak thumb pad present; a more definite round palmar callus; 

 metacarpal tubercles well developed. Toes long, third toe longer than 

 fifth, its disk reaching to base of antepenultimate phalanx of fourth; 

 disk of fourth toe covering one-eighth the tympanum and approxi- 

 mately equal to that of third finger; a distinct oval inner metatarsal 

 tubercle and a smaller round outer one; a blunt tarsal ridge, ending 

 at heel, with a tubercular swelling midway; a distinct skinfold on 

 heel and knee. Body elongate, in postaxillary region a little less than 

 greatest width of head. When hind leg is adpressed, heel reaches 

 center of eye; when limbs are laid along the sides, knee and elbow 

 touch; when hind legs are bent at right angles to body, heels slightly 

 overlap. Skin of upper parts finely granular, with some coarse granules 

 on sacrum, on upper surface of legs, and behind anus; venter smooth, 

 with a few fine diagonal striations on proximal part of posterior femur; 

 a glandular swelling from posterior corner of eye extending across 

 upper posterior part of tympanum and ending behind it; no skinfold 

 across the chest; no ventral disk; external vocal sacs in the male 

 indicated by lateral skinfolds at sides of chin. 



Dimensions. — Head and body, 21 mm.; head length, 7 mm.; head 

 width, 6.5 mm.; femur, 9 mm.; tibia, 10.5 mm.; foot, 8.5 mm.; hand, 

 6 mm. 



Color in alcohol. — Dorsum black, with a narrow slate-gray dorsolat- 

 eral line beginning at snout tip, continuing on canthus and upper 

 eyelid and above tympanum, and lightening to pearl gray on the side, 

 where it ends in a large oval pearl gray spot on upper anterior femur; 

 a similar pearl gray spot in axilla, continuing on lower surface of upper 

 arm to elbow, and another one on concealed surface of tibia behind 

 and below the knee; venter black, with a fine gray reticulation on 

 posterior half of belly and a gray patch on lower inner halves of femora 

 united on the midline; side of head black, with a fine pearl gray line 

 beginning as a small crescentic mark on tip of snout, touching lower 

 edge of nostril, crossing lip diagonally and ending above shoulder; 

 soles of feet and palms of hands black, their disks and tubercles 

 lightening to drab-gray. 



Remarks. — The structure and markings of this form are rather like 

 those of Dendrobates lugubris, but numerous differences can be noted. 

 The adult D. hahneli is smaller; the pale axillary spot does not exist 



