98 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
strongly convex and prominent basally, faintly convex and ascending 
terminally. Nostril exposed, small, longitudinally broadly oval, mar- 
gined above by a narrow extension of the membraneous integument 
of nasal fossa, an internal tubercle showing conspicuously in posterior 
portion. No trace of rictal bristles, and feathers of chin without 
terminal sete. Wing moderate, very much rounded, but longest 
primaries extending decidedly beyond secondaries; sixth and seventh, 
fifth and sixth, or fourth, fifth, and sixth primaries longest, the tenth 
(outermost) between one-half and three-fifths as long as the longest, 
the eighth slightly longer, the ninth decidedly shorter, than secondaries. 
Tail about four-fifths as long as wing, much rounded (graduation not 
greater than length of culmen), the rectrices (12) broad, rounded 
terminally. Tarsus about two-fifths as long as wing, rather slender, 
the acrotarsium distinctly scutellate, the planta fused (sometimes 
indistinctly scutellate on outer side); middle toe, with claw, much 
shorter than tarsus, but decidedly longer than whole culmen; outer 
toe, without claw, reaching to or slightly beyond middle of subter- 
minal phalanx of middle toe, the inner toe slightly shorter; hallux 
shorter than inner toe but much stouter; basal phalanx of middle toe 
wholly or for much the greater part united to outer toe, about half 
united to inner toe; claws moderate in size and curvature, that of the 
hallux decidedly shorter than the digit. Plumage full and blended, 
that of rump and flanks more lengthened and lax; loral, rictal, and 
orbital regions—sometimes forehead and crown also—naked, the 
crown with sparse hair-like feathers or bristles. 
Coloration.—Adult males uniform black, the wing-coverts (at least 
some of the lesser coverts) tipped with white, the back sometimes 
with a small concealed patch of white; adult females and young 
males brown above, tawny or rufescent below; bare skin of head 
light blue in life (in both sexes). 
Range.—Honduras to Colombia. (Two species.) 
KEY TO THE SPECIES AND SUBSPECIES OF Q@YMNOCICHLA. 
a. General color black. (Males.) 
b. Forehead, lores, and more or less of crown nude. (Adult males.) 
c. Anterior margin of lesser wing-covert area mostly black; bill black. (Gymno- 
cichla nudiceps.) 
d. Deeper black, the posterior under parts black; smaller under wing-coverts 
mostly wholly black. 
e. Smaller (averaging: wing 76.4, tail 57.7, culmen 20.6, tarsus 29.4). (East- 
ern Panamé and adjacent parts of northwestern Colombia.) 
Gymnocichla nudiceps nudiceps, adult male (p. 99). 
ee. Larger (averaging: wing 78.9, tail 61.7, culmen, 20.9, tarsus 30). (North- 
western Panama and western Costa Rica.) 
Gymnocichla nudiceps erratilis, adult ‘male (p. 101). 
