mm. long and 1.8 mm. wide. Lip small, simple, lightly 
arcuate-recurved with erect sides and about 4 mm. long 
in natural position, lanceolate-ovate, acute, rounded at 
the base, 8-nerved and 1.8 mm. wide when expanded, 
minutely cellular-pubescent. Column small, denticulate 
at the truncate apex, about 2.1 mm. high at the back, 
extended in front at a right angle into a prominent fleshy 
foot. 
This species is allied to Pleurothalls citrina Schitr., 
but has larger flowers and a dissimilar lip. 
Cuzco: Prov. of Urubamba, Salapunco (kil. 84), at 2400 meters 
altitude, on rocks growing with moss, March 25, 1946, C. Vargas 
5989 (Tyrer in Herb. Ames No. 63356). 
Pleurothallis caudatipetala C. Schweinfurth in 
Bot. Mus. Leafl. Harvard Univ. 10 (1942) 175, pl. 22, 
figs. 5-8. 
A recent and more fully developed collection of this 
little species shows several vegetative differences from 
the apparently juvenile type originally described. 
The caespitose plants are about 8-8.5 (not 1.5 cm. or 
less tall, as specified). Leaves larger than noted, up to 
15 mm. long. Inflorescences much surpassing the leaf 
(instead of shorter than or subequaling the leaf), loosely 
racemose, up to 11-flowered (rather than 1- to few- 
flowered). Flowers more glabrous than those of the 
type. Although no notes of the color are given, all but 
the basal portion of the sepals and petals is dark purplish 
in the dried specimen. 
Cuzco: Prov. of Urubamba, Machupicchu, at 2040 meters altitude, 
on rocks, April 16, 1943, C. Vargas 3367. 
Pleurothallis crateriformis C. Schweinfurth sp. 
nov. 
Herba epiphytica, caespitosa, mediocris. Caules pa- 
tentes, graciles, vaginis tribus arcte tubulatis pubescen- 
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