'J't^OPICAL AMERICAN ORCHIDS 
acuminatum valde deflexum contracto. Discus prope basim 
callo permagno ceroso ornatus. Columna abbreviata. 
Roots coarsely fibrous. Stems up to 8 cm. long, slender, 
entirely concealed by tubular bracts and the sheaths of the 
leaves. Leaves 10--14..'5 cm. long, up to 2.2 cm. wide, usually 
three, approximate, crowded near the summit of the stem, 
ligulate, gradually narrowed toward the obtuse bilobulate 
apex, coriaceous, ascending. Peduncle up to 18 cm. long, 
clothed with elongated ancipitous closely appres.sed sheath¬ 
ing bracts, loosely paniculate, with the divisions of the 
panicle 2.5-3.5 cm. long. Flowers olive green with purple 
markings. Pedicel with the ovary about 3 mm. long. 
Lateral sepals about 4 mm. long, forming a blunt menturn 
which is 2 mm. long, broadly ovate, acute, reticulate-nerved, 
with the middle nerve more or less prominent on the outer 
surface. Dorsal sepal 4 mm. long, narrower than the 
laterals, oblong, acute. Petals 3 mm. long, narrowly spatu- 
late, emarginate at the apex or unequally bidentate. La- 
bellum 3.5 mm. long, about 3 mm. wide across the lateral 
lobes, dilated to about the middle from a cuneate base, tri- 
lobed in front, with the lateral lobes much smaller than the 
terminal lobe; lateral lobes obtuse; middle lobe rounded, 
abruptly contracted into an acuminate tip. Disc with a large 
conical waxy callus at the base. Column about 3 mm. long. 
Polystachya Powellii, in habit, resembles P. luicola 
Hook., but is quite different from it in the structure of the 
labellum. It differs from P. lincata Reichb. f. in having 
smaller flowers and in having the middle lobe of the labellum 
subequal to the lateral lobes and abruptly contracted into a 
slenderly acuminate tip. 
Panama, Province of Ghiri({ui, west side of Caldera 
River, in gulch opposite Lino, C. W. Powell 343. Flowering 
at Ralboa under cultivation in September 1923. Lip very 
fuzzy, as if it were frosted. 4000 feet altitude. (Type in 
Ilerlx Ames No. 27177.) 
Rolfea Powellii Ames sp. nov. Ilerba terrestris, elata, 
foliosa. Radices valde libratae, amplae. Caules erecti, 
graciles. Folia papyracea, prominenter nervosa, in petiolos 
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