TROPICAL AMERICAN ORCHIDS 
about 2 mm. in diameter, slender, rigid, partly concealed by 
tubular sheaths, monophyllous. Sheaths three; the upper¬ 
most one 2.7-3.4 cm. long, slightly dilated upward, nervose, 
brownish; the lowermost one abbreviated and soon breaking 
down into spreading fibres. Leaf 11-12 cm. long, up to 
1.5 cm. wide, oblanceolate, contracted into a slender petiole, 
bilobulate at the tip with a short apiculate projection be¬ 
tween the lobules. Peduncle solitary, including the raceme 
up to 3 dm. long, closely oppressed to the petiole, with a 
short spathaceous bract at the base, below the raceme pro¬ 
vided with several closely oppressed tubular bracts. Raceme 
about 15 cm. long, bearing from ten to fifteen dull maroon 
second flowers. Bracts of the raceme about 5 mm. long, 
tubular, acute. Pedicellate ovary 4-8 mm. long, ascending 
or at length deflexed. Lateral sepals 14 mm. long, coherent 
almost to the apex, forming a narrowly lanceolate lamina 
which is minutely and densely glandular in the middle and 
densely hairy on each side on the upper surface and con¬ 
spicuously bicarinate beneath. Dorsal sepal about 14 mm. 
long, 3 mm. wide near the middle, narrowly lanceolate, 
acute, spar.sely hairy near the margin on the upper surface, 
strongly carinate along the middle on the outer surface 
with the keel extending to the apex. Petals 2 mm. long, 
1.5 mm. wide below the middle, broadly asymmetrically 
ovate, acute, produced anteriorly at base into a triangular 
protuberance which is decurrent along the foot of the 
column, 1-nerved. Labellum 5 mm. long, about 2 mm. 
wide, unguiculate, 3-lobed in front of the narrow claw; 
lateral lobes abbreviated, about 1 mm. long, produced an¬ 
teriorly into a small obtuse porrect lobule; middle lobe 4 
mm. long, oblong, obtuse, 3-nerved, with the nerves promi¬ 
nent beneath near the base. Disc tricarinate; median keel 
about 2 mm. long, much thickened, sulcate on the top and 
forcipate in front; lateral keels membranaceous, 2 mm. 
long, inclined, with the inner margins contiguous or over¬ 
lapping each other in front. Column 3.5 mm. long, dilated 
upward, with a conspicuous wing on each side at the summit, 
the wings finely denticulate on the upper margin. 
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