Measurements (in mm.).—Snout to vent, 58; leg, 86; head length, 20; head width, 18.6.
Arms rather short, upper arm slender, forearm much thickened; a small axillary web present; disks on three outer fingers distinctly larger than tympanum, of first finger equal to or somewhat smaller than tympanum; outer fingers, between one-third and one-half webbed; on inner fingers webbing less than one-third; first finger more or less opposed to other three, its base widened, and the upper surface covered by a large patch of minute dark, horn-colored nuptial asperities, that extend to near the terminal disk; subarticular tubercles strongly elevated with numerous supernumerary tubercles on palm; a somewhat enlarged elevated palmar tubercle; under surface of forearm with a row of distinct tubercles; other smaller scattered granules present. Toes more than four-fifths webbed, the membrane reaching the base of the terminal disks, on one side at least, of all toes save fourth; subarticular tubercles strongly elevated, with numerous supernumerary tubercles on sole; a large elevated inner metatarsal tubercle; a small outer tubercle; a continuous, well-defined, tarsal fold extending entire length of tarsus. Tibiotarsal articulation reaches nostril when leg is brought forward.
Color and marking.—General color of type (preserved in formalin, then transferred to alcohol) dull grayish purple, darker anteriorly and somewhat lighter and more mottled posteriorly; color very much lighter on sides with a few cream, dark-edged spots in groin and on sides of abdomen; front and back surfaces of thigh and shank with some darker and lighter flecking that is continued more or less on the foot. When submerged in water, very dim dark spots or bars visible on limbs; ventral surface dirty brownish flesh, without markings.
Variation.—The series consists of five adult male specimens. It is presumed that the female is considerably larger, and may lack the nasal proboscis which I suspect is a secondary sexual character.
There are some differences in the shade of coloring in the preserved specimens, some being darker, some lighter than the type. In two the lateral dark-edged, cream spots extend to the axilla, and the light and dark markings on the front and back surfaces of the leg are much more distinct in most of the specimens than in the type. When the specimens are submerged in water, the black bars on the limbs are evident in all specimens. The tympanum is sometimes darker, sometimes lighter than its surroundings.
In the field notes of Mr. Dalquest I find the statement that the color in life is bright yellow, which presumably applies to all of the specimens. No trace of this color remains at the present time.
The ventral granules of some of the paratypes are very unequal in elevation, some being elongated, nipplelike.
The following table gives the variation in measurements of the type and paratypes: