TROPICAL AMERICAN ORCHIDS 
apex with a subacute point, 3-nerved. Labellum broadly 
quadrate-triangular in outline, 5-lobed with the terminal 
lobe bilobed, about 7.2 mm. long and 1 cm. broad at base 
when expanded; basal lobes retrorse, triangular-lanceolate, 
oblique, up to 4 mm. long on the posterior margin, rounded 
at the apex; intermediate lobes short, triangular, spreading, 
acute; terminal lobe quadrate, with nearly parallel sides, 
deeply bilobed, about 3.2 mm. long. Disc provided with a 
basal linear-oblong callus which is thick at its base, thinner 
in its central portion, and fleshy much-thickened in its 
anterior part, and with two callose teeth on each side of and 
in front of the callus. Column short, extended on each side 
into two spreading suborbicular inconspicuously denticulate 
wings. 
In the structure of the labellum Lockhartia triangulabia 
appears to be unique. The subfalcate shape of the leaves 
is also unusual. 
Panama, Province of Chiriqui, C. W. Powell 362a. 4000- 
5000 feet altitude. (Type in Herb. Ames No. 28193.) 
Lockhartia variabilis A. & S. sp. nov. Herba humilis, 
variabilis. Caulis basibus foliorum imbricatis omnino ob- 
tectus. Folia disticha, scapelliformia, leviter falcata, obtusa. 
Flores flavi, in sicco membranacei. Sepala elliptico-lanceo- 
lata, mucronata. Petala elliptica, latiora, acuta. Labellum 
in circuitu quadratum, basi rotundatum, medio rhombico- 
dilatatum, deinde angustatum, apice bilobatum; discus basi 
callosus. Columna late alata. 
Plant low for the genus, 14 cm. tall to the apex of the 
uppermost leaf. Roots fibrous, glabrous. Stem compressed, 
entirely concealed by imbricating leaf-bases. Leaves dis¬ 
tichous, equitant, scalpelliform, slightly spreading-falcate, 
narrowed to an obtuse apex, up to 3.35 cm. long on the lower 
margin, 2.6-6.5 mm. wide near the base (the lowest leaves 
not 2 cm. long, 4.5 mm. wide). Inflorescences apparently 
single in the axils of the two uppermost leaves. Flowers mem¬ 
branaceous when dry. Lateral sepals elliptic- or oblong- 
lanceolate, 3.9-4.9 mm. long, about 2 mm. wide below the 
middle, 1- or 3-nerved, mucronate. Dorsal sepal similar. 
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