ORCHIDACEAE QUAEDAM AMERICANAE 
anguste elliptico-oblongum, apice bilobulatum cum apiculo 
interjecto, basi attenuatum. Pedunculus filiformis, uni- 
florus, folium excedens. Flores flavidi. Sepala lateralia 
fere usque ad apicem cohaerentia, laminam anguste el- 
lipticam formantia. Sepalum dorsale basi valde concavum, 
apice subacutum, quam lamina sepalorum lateralium an- 
gustius, trinervium. Petala late et irregulariter obovata, 
acuminata, acuta. Labellum oblongum, obtusum, apice 
minute papillosum. Columna utrinque stelidio acuto. 
Plants similar in habit to Pleurothallis Brighamii S. 
Wats. Roots fibrous, slender, whitish. Secondary stems 
caespitose, monophyllous, abbreviated, about 4 mm. long, 
clothed by three brownish sheaths, the uppermost one of 
•which is dilated, much longer than the others, exceeding 
the stem and conspicuously nerved. Leaf with the petiole 
1.5-3 cm. long, marginate; lamina 1-2 cm. long, 4-6 mm. 
wide, inconspicuously bilobulate at the tip, with an apicule 
between the lobules, narrowly oblong-elliptical, fleshy, 
with the mid-nerve prominent beneath; petiole slender, 
sulcate. Peduncle solitary at the summit of a secondary 
stem, 3-4 cm. long, very slender, erect, bearing a single 
yellow flower. Bracts subtending the pedicel 2.5 mm. 
long, tubular, dilated upward. Pedicel with the ovary 
about 9 mm. long, very slender. Lateral sepals 5 mm. long, 
coherent almost to the tip, forming a narrowly elliptical 
4-nerved lamina 1.75 mm. wide, mid-nerve of each sepal 
forming a conspicuous keel on the outer surface; each mem¬ 
ber of the synsepalous lamina is apparently 2-nerved, with 
an inconspicuous nerve near the line of cohesion. Dorsal 
sepal 5 mm. long, subequal to the laterals, strongly concave 
at the base, 3-nerved, subacute. Petals about 2.25 mm. 
long, 1 mm. wide, unequally obovate (the anterior margin 
more protuberant than the posterior), acuminate, acute, 
with a posteriorly situated apicule, 1-nerved. Labellum 
2 mm. long, oblong-lingulate, ascending from the tip of 
the column-foot then sharply curved forward, somewhat 
conduplicate at the base, obtuse and minutely papillose 
at the apex, ecallose. Column 1.5 mm. long, produced 
into a foot which is 1 mm. long, 3-toothed at the summit, 
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