serrulatis; discus trinervius, conspicue  bilamellatus. 
Columna brevis, arcuata, antice valde concava, circiter 
3 mm. alta, in pedem prope 2 mm. longum producta. 
This plant has two allied species which are especially 
similar in vegetative characters. It differs from Pleuro- 
thallis frutex Schltr. in all of the floral segments and from 
P. hystrix Reichb.f. in the shape of the petals and lip. 
ford 
British Guiana: Serra Acarai, on rocky hill top, 7 miles east of 
Onoro, epiphytic on low tree, about 4 feet from the ground, October 
2, 1952, Forestry Department, Field No. G 340, Record No. 7316 
(Type in N.Y. Botanical Garden). 
Plieurothallis scandens 4 mes var. simplicicaulis 
C. Schweinfurth var. nov. 
Herba epiphytica, caulibus simplicibus et floris colore 
diversa a specie differt. 
Plant epiphytic, caespitose. Stems numerous, simple, 
apically unifoliate, up to 25 cm. high, entirely concealed 
by close, tubular, dark-pubescent sheaths. Leaf linear- 
lanceolate to oblong-linear, up to 10.7 cm. long and 8 
mm. wide, generally somewhat broader than that of the 
type. Flowers very similar to those of the type, but of 
a different color, and with asomewhat more prominently 
ciliolate lip. The altitude of these collections is distinctly 
higher than the average habitat of the typical form. 
VENEZUELA: State of Bolivar, Sororopan-tepui, 1500-1700 m. alt., 
frequent epiphyte on middle slopes, flowers bronze-yellow, December 
16, 1952, Bassett Maguire & John J. Wurdack 33836,—Chimanta Mas- 
sif, Torono-tepui, in Clusia forest on slopes of Middle Falls of Rio Ti- 
rica, below Summit Camp, at 1760-1880 meters altitude, on tree 
branch, leaves coriaceous, deep green above and paler beneath, sepals 
and petals tawny yellow, the dorsal one with a central pale lavender 
stripe, lip dark maroon, column dull lavender at the base, cream- 
white at the apex, March 1, 1955, Julian A. Steyermark & John J. 
Wurdack 1210.—Same locality, on densely forested slopes between 
the upper reaches of Rio Tirica (left-hand fork) and Riscobel Ledema 
Camp, southeast portion of Apdcara-tepui, at 1700-1850 meters alti- 
tude, leaves coriaceous, deep green above and paler beneath, flowers 
yellow and madder purple, June 23, 1953, Steyermark 75957 (Tyrr 
in Herb. Ames No. 69583). 
[ 16 ] 
