Hvuanuco: Churubamba District, Hacienda Mercedes, Cotirarda, 
epiphytic on tree trunks, at 1560 meters altitude, September 21, 
1936, Ynes Mexia 8215a. (Tyrer in Herb. Ames No. 46837). 
Pleurothallis dilatata C. Schweinfurth sp. nov. 
Herba mediocris, rhizomate adscendente. Caules ap- 
proximati, trivaginati, vaginis tubulatis evanidis obtecti. 
Folium unicum, elliptico-oblongum, apice rotundatum, 
ad basim angustatum, in sicco valde coriaceum. Inflores- 
centiae unicae vel duae, folium conspicue superantes, 
usque paene ad basim racemosae. Flores majores. Sepal- 
um dorsale oblongo-oblanceolatum, obtusum, _ triner- 
vium, intus supra pubescens. Sepala lateralia faleato- 
decurva, in laminam elliptico-ovatam bilobatam connata, 
intus supra pubescentia. Petala sepalis breviora, falcato- 
spathulata, apice rotundata, trinervia. Labellum valde 
arcuatum, expansum basi apiceque anguste oblongum et 
medio ovato-dilatatum, apice rotundatum. Columna 
gracilis, arcuata, in pedem conspicuum producta. 
Plant medium-sized, with an ascending rhizome, up 
to 18.5 cm. tall. Roots numerous, fibrous, glabrous. 
Stems approximate, up to 6.5 cm. tall, concealed by 
three tubular evanescent sheaths, plurisulcate in the dried 
specimen. Leaf solitary, elliptic-oblong, rounded at the 
apex with a minutely tridenticulate tip, cuneate-nar- 
rowed to a sessile base, up to 7.5 cm. long and about 1.5 
em. wide, thickly coriaceous, finely punctate beneath in 
the dried specimen. Inflorescences one or two, axillary, 
suberect to flexuous, much exceeding the leaf, up to 13.5 
cm. long, loosely racemose nearly to the base. Floral 
bracts infundibuliform, scarious, acute, glabrous, much 
shorter than the pedicellate ovary. Flowers rather large 
for the plant, with sepals spreading. Dorsal sepal oblong- 
oblanceolate, 10—10.5 mm. long, 8.1—8.2 mm. wide, ob- 
tuse, 3-nerved, finely short-pubescent within (except 
near the concave base) and on the margins, carinate 
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