dle. Lateral sepals united to about the middle, gibbous at 
the base, obliquely triangular-lanceolate, acuminate, de- 
curved, dorsally prominently carinate along the solitary 
nerve, 4-5 mm. long, 2—2.5 mm. wide across the united 
basal portion. Petals obliquely oblong, broadly rounded 
at the apex, 1-nerved, 2—2.5 mm. long, 0.8—1 mm. wide. 
Lip with a short claw, arcuate in natural position, has- 
tately 8-lobed when spread out, 3-nerved with the nerves 
extending slightly above the middle of the lip, 3-8.2 
mm. long including the claw, 1.8-2.2 mm. wide across 
the lateral lobes; lateral lobes broadly rounded, slightly 
thickened on the apical margins; mid-lobe oblong-quad- 
rate, subtruncate at the apex, about 1 mm. wide. Column 
short, stout, fleshy, tridentate at the apex, 2 mm. long, 
with a foot about 1 mm. long. Capsule obliquely glo- 
bose, about 4 mm. long. 
This species is unique among the Guatemalan species 
of Pleurothallis in that it has a subequally three-lobed 
lip. There seems to be no closely allied species in Central 
America. The Jamaican Pleurothallis trilobata Fawe. & 
Rendle has a similarly shaped lip. However, that species 
is a minute plant less than 1 cm. tall and the lip is only 
about one half as long as that of P. crucilabia. 
GuaATEMALA: Guatemala, Volean de Pacaya, above Las Calderas, 
alt. 1800-2400 m., Nov. 30, 1938, P.C. Standley 58433 (Tyre in Herb. 
Field Mus. No. 974102). 
Pleurothallis triangulipetala Ames & Correll sp. 
nov. 
Herba parva, epiphytica, caespitosa, erecta. Caulis 
gracilis, unifoliatus, vaginis lepanthiformibus obtectus; 
vaginae tubulatae, costis prominentibus hispidis, in api- 
cem acuto-apiculatum hispido-ciliatum dilatatae. Folium 
a petiolo brevi suleato suborbiculare vel late ellipticum, 
obtusum vel retusum et cuspidatum, marginatum, glab- 
rum, coriaceum. Pedunculi plures, filiformes, glabri, cum 
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