TROPICAL AMERICAN ORCHIDS 
minate at base in a narrow black band. Panicle with approx¬ 
imately seven short ascending branches which are 1.8 
(rarely .6) -3.7 cm. long. Floral bracts minute, triangular, 
concave. Flowers very small. Lateral sepals free, obliquely 
obovate, about 4.1 mm. long, 2-2.2 mm. wide, subunguicu- 
late-narrowed below, obtuse above, and dorsally carinate 
near the apex. Dorsal sepal suborbicular, 3.1-3.5 mm. long, 
about 2.5 mm. wide, strongly concave, rounded at the apex, 
with an indistinct dorsal apicule, slightly narrowed toward 
the base. Petals oblong to obovate-oblong, oblique, about 
4 mm. long, 2-2.15 mm. wide, abruptly and broadly trun¬ 
cate, somewhat narrowed toward the base. Labellum about 
8 mm. long, deeply 3-lobed; lateral lobes retrorse, oblong, 
falcate toward their apex, gradually narrowed to the slender 
but short isthmus; isthmus about 1.2 mm. wide, flabellate- 
dilated into the anterior lobe; middle lobe flabellate-reni- 
form, 6-6.8 mm, wide, rather deeply bilobed but the lobes 
contiguous. Disc minutely papillose throughout, at the 
base a broad transverse keel in front of which are three small 
calli, the middle one of which is largest and subtrilobed. 
Column very short and stout, about 1.1 mm. long dorsally, 
with only rudimentary processes instead of wings. 
Oncidium ebrachiatum appears very similar to 0. teres 
A. & S., but the lip is differently shaped, the callus very 
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