NEW OR NOTEWORTHY ORCHIDS 
somewhat spongy more or less dorso-ventrally flattened 
apical half. In S. crescentiicola the apical half is variable in 
length and breadth, and sometimes, perhaps by injury or in 
dried specimens by desiccation, may become obsolescent, 
the tendency toward obsolescence being by no means uni¬ 
form in the same plant. From the description of Stelis 
praemorsa it would seem that the flowers studied were in 
this latter category. 
Panama. 
Stelis Williamsii Ames Orchidaceae 7 (April 1922) 
133. 
Stelis collina Schltr. in Fedde Repert. Beihefte 17 
(December 1922) 15. 
This species, which is in part distinguished by the 
glandulose upper margin of the petals and by purplish 
flowers, is represented in my herbarium by the type collected 
in Cana by R. S. Williams and by a duplicate of Powell’s 
180, on which Schlechter relied in drawing up his description 
of Stelis collina. Structurally S. Williamsii and S. collina 
are identical, although in Powell’s 180 the sepals are slightly 
shorter than in the type of S. Williamsii. 
Panama. 
Pleurothallis alpina Ames sp. nov. Caules secundarii 
caespitosi, triangulares, longitudinaliter sulcati, erecti, basi 
vaginis brunneis chartaceis vestiti, monophylli. Folium 
valde coriaceum, elliptico-lanceolatum, apice bidenticulatum 
apiculo interjecto. Flores mediocres, in axilla fold congest!. 
Pedunculi tri- vel quadriflori, e bractea spathacea orientes. 
Bracteae flores subtendentes infundibuliformes. Sepala 
lateralia demum libera, valde coriacea, margine minute 
glandulosa, oblongo-lanceolata, acuta, extus per medium 
carinata, carina minute scabridula, trinervia. Sepalum 
dorsale oblongum, supra medium usque ad apicem an- 
gustatum, incrassato-carnosum, extus per medium carina- 
tum. Petala membranacea, oblonga, apice angustata, in 
acumen brevem producta, margine supra medium sparse et 
irregulariter denticulata, trinervia, sepalis multo breviora. 
14 
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