TROPICAL AMERICAN ORCHIDS 
Costa Rica, Cachi, C. H. Lankester 915. (Cultivated 
at Cartago and flowered in June 1924.) Flower dusky vi¬ 
nous purple, upper sepal “hyalinaceous,” especially the mar¬ 
gins. Lip deep vinous purple. Column white, anther cream 
color. (Type in Herb. Ames No. 28690.) 
Pleurothallis segregatifolia A. 5. sp. nov. Herba 
nana. Caules minuti, caespitosi, monophylli. Folia sub- 
orbicularia vel obovata, apice rotundata, interne plus mi- 
nusve cuneato-angustata. Inflorescentiae folia erecta multo 
superantes, sub folia orientes. Racemi laxe pauciflori. 
Sepala lateralia oblique semiovata, per dimidium basalem 
connata, apice cucullato-obtusa. Sepalum dorsale elliptico- 
oblongum, cornu obtuso terminans. Petala falcato-linearia, 
breviora. Labellum expansum cuneato-obovatum, trilo- 
batum. 
Plant dwarf, 4-7.5 cm. tall. Roots stout for the plant, 
fibrous, flexuous, glabrous. Stem minute, caespitose, 4-6 
mm. (rarely up to 9 mm.) long, monophyllous, invested be¬ 
low with tubular scarious sheaths. Leaf suborbicular to obo- 
vate or cuneate-spatulate, 6 mm. (rarely 12 mm.) long, com¬ 
monly 4-5 mm. wide, rounded and minutely 3-denticulate 
at the apex, more or less cuneate-narrowed below, margined, 
fleshy in the formalin material, coriaceous when dry, the 
mid-nerve prominently sulcate above and carinate beneath; 
petiole 1-6 mm. long, channelled, gradually mei'ging into 
the cuneate leaf-base. Inflorescences much surpassing the 
leaf, inserted 2-4 mm. below the leaf, one to several to a 
stem. Peduncles filiform, 1.9-4.4 cm. (usually about 3 cm.) 
long below the raceme. Raceme suberect or flaccid, 1-3.2 
cm. long at maturity, loosely flowered. Rachis fractiflex. 
Floral bracts minute, infundibuliform. Flowers up to eleven 
(usually less), membranaceous. Lateral sepals obliquely 
semiovate, connate about to their middle, forming a distinct 
mentum with the column-foot, about 3.8 mm. long, free part 
1.6 mm. wide below, obtuse at the cucullate tip, carinate 
without, 2-nerved. Dorsal sepal elliptic-oblong, terminating 
in a hollow obtuse horn, 3.8-4.2 mm. long, 1.5 mm. wide, 
3-nerved, dorsally carinate. Petals linear-falcate, about 3 mm. 
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