CENTRAL AMERICAN ORCHIDS 
tended at the base into a short foot to the tip of which the 
labellum is rigidly attached. Pollinia four, cohering in pairs 
at the apex of an oblong caudicle. 
Allied to Ornithidium Biolleyi Schltr. and 0. bracteatum 
Schltr., from which it is very dilferent in the structure of 
the floral segments. 
Costa Rica, San Cristobal, C. H. Lankester & Alfredo 
Sancho 421, January 12, 1923. Common on trees standing 
in the pastures on ridges or upper slopes, a delightful 
natural object. Lower leaves deciduous. Segments of the 
flower crystalline white, petals suffused centrally at base 
with pink. Labellum empire-yellow (Ridgway), basal two- 
thirds of column aster-purple (Ridgway), this color also 
tinging the lateral lobes of the labellum. Anther-cap white. 
5500 feet altitude. (Type in Herb. Ames No. 23735.) 
Oncidium Lankesteri Ames sp. nov. Est planta 
habitu 0. suavis Lindl. pseudobulbis et foliis minor (Lan¬ 
kester). Pseudobulbi et folia desiderantur. Inflorescentia 
decemramosa, rami sex ad septemflori, patentes vel leviter 
ascendentes. Bracteae ramos subtendentes permagnae, 
arete appressae. Bracteae inflorescentiae flores subtendentes 
late triangulari-ovatae, scariosae, pedicellis multo breviores. 
Sepala lateralia unguiculata, oblonga, undulata, valde 
carinata. Sepalum dorsale unguiculatum, oblongum, acu- 
tum, ecarinatum. Petala oblongo-elliptica, obtusa, vix un¬ 
guiculata. Sepala petalaque brunnea, marginibus lutea. 
Labellum panduratum; lobis lateralibus suborbicularibus; 
lobo medio obreniformi, emarginato, aureo, isthmo brunneo- 
maculato. Crista quinquelobata. Columna alis dolabri- 
formibus instructa. 
Pseudobulbs and leaves as in Oncidium suave Lindl., but 
smaller. Inflorescence up to 9 dm. long, racemose-paniculate, 
the lateral branches up to ten, 14-19 cm. long, each branch 
6-7-flowered, with the flowers 2.5-3 cm. apart. Bracts sub¬ 
tending the branches about 1.3 cm. long, scarious, breaking 
down into fibres, closely oppressed. Bracts subtending the 
flowers about 5 mm. long, scarious, broadly triangular- 
ovate. Pedicels with the ovary 2-2.5 cm. long. Lateral 
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