NEW OP. NO'i'iavoirniY ()iu:iiids 
Stelis vestita is closely allied to S. Endresii Heichb. f., 
from which it differs conspicuously in having much smaller 
flowers. From S. glandulosa Ames it differs in the shape of 
labellum, which is conspicuously glandular-pubescent on the 
basal half and in having much smaller flowers. 
Costa Rica, Zarcero, C. H. Lankester A Oton Jimenez 
460, April 1923. Sepals dull purple, with a narrow hyaline 
margin. Leaves very thick and succulent. BoOO feet alti¬ 
tude. (Typh in Herb. Ames No. 26959.) 
Pleurothallis dichotoma Ames sp. nov. Radices 
(ibratae, albidae, glabrae. Rhizoma abbreviatum. Caules 
secundarii dense caespitosi, valde abbreviati, vaginis panels 
scariosis vestiti. .Folium oblanceolalum, bene marginatum, 
apice bidenticulatum apiculo interjecLo, in petiolum an- 
gustatum contractum. Pedunculus cum racemo folia 
multo excedens, valde gracilis. Inllorescentia laxe dicho¬ 
toma, plus minusve quinqueflora. Rractcae inflorescentiae 
infundibuliformes, acutae, scariosae, pcdicellis breviores. 
Sepala lateralia vix usque ad medium cohaerentia, jiurpurea, 
lanceolata, in caudam fihformem llavidam producta, bi- 
nervia, extus per medium carinata. Sepalum dorsale simile, 
purpureo-striatum, trinervium nervis extus prominentibus, 
basi valde concavum. Petala lanceolata, bene purpureo- 
fimbriata, in apicem liliformem producta, uninervia. La¬ 
bellum subsagittatum, valde obtusum, supra medium 
glandulosum, marginc glanduloso-timbriatum, subtus prope 
basim valde carinatum, ecallosum. Columna brevis. 
Roots fibrous, whitish, smooth. Rhizome abbreviated. 
Secondary stems densely' caespitose, about 4 mm. long, 
concealed by about two scarious tubular sheaths. Leaf 
oblanceolate, t.3-2.4 cm. long, up to 4 mm. wide above the 
middle, marginate, bidenticulate at the apex with an- 
apicule between the teeth, contracted below into a slender 
petiole. Peduncle with the raceme up to 6 cm. long, slender, 
thread-like. Inflorescence about 2.5 cm. long, dichotomous, 
loose, about 5-flowered. Lateral sepals coherent hardly to 
the middle, 8 mm. long, 1 mm. wide below the middle, 
lanceolate, with the apex slenderly caudate and about 4 mm. 
58 
