152 Proceedings of the Biological Society of Washington. 



Ornithocephalus lanuginosus, sp. nov. 



Herba parvula, epiphytica, acaulescens, circa 10 cm. alta. Radices 

 numerosae, glabrae, flexuosae, graciles. Folia equitantia, scalpelliformia, 

 rigida, erecta et patentia, vaginis dense congestis et imbricantibus, 

 articulata, nunc falcatula, oblique acuta, in sicco rugulosa et flavo-viridia, 

 usque ultra 23, plus minusve 4.5 cm. longa, 6-7 mm. lata. Inflorescentiae 

 laxissimae, in visu foliis breviores (sed abruptae), dense lanuginosae, in 

 parte superiore floriferae. Pedunculi vaginis singulis vel duabus perlaxe 

 infundibuliformibus ornati. Bracteae inflorescentiae reflexae, ovatae, 

 ciliatae, dorso medio alte carinatae, carina plus minusve erosa. Flores 

 minuti, perianthio membranaceo. Sepala petalaque similia. Sepala 

 lateralia orbicularia, margine eroso-ciliata, uninervia et dorso medio 

 conspicue carinata, carina irregulariter eroso-ciliata, extus sparsim pilosa, 

 circa 2 mm. longa et lata. Sepalum dorsale simile, a basi late cuneata 

 suborbiculare, acutum, circa 2 mm. longum. Petala oblique suborbicularia, 

 margine erosula, dorso verosimiliter carinata, circa 1.9 mm. longa et lata. 

 Labellum trilobatum, lobi laterales inconspicui, valde recurvati, extensi 

 spathulati, circa 1.35 mm. longi, papillosi; lobus intermedius angustissime 

 linearis, in positu naturali valde antrorsum curvatus, conduplicatus, dorso 

 carina tus, acutus, extensus circa 5 mm. longus; discus medio callo maximo 

 crasso piano omnino obtectus. Columna minuta, rostello perlongo curvato 

 ornata. Ovarium densissime lanuginosum. 



In specimens collected by J. F. Cowell (298), March 4, 1905, at Gatun, 

 Panama, the racemes bear smaller flowers than those described above. 



Ornithocephalus lanuginosus is related to 0. myrticola Lindl., and to O. 

 bryostachyus Schltr. It difi^ers from 0. tnyrticola in its relatively narrower 

 sepals and ovate-lanceolate, simple labellum; from 0. bryostachyus it differs 

 in its broader leaves and in the shorter labellum with different lobes. 



PANAMA, Province of Panama, edge of forest along Panama-Pecora 

 Road, near Tecumen River. Killip 3314, December 30, 1917. 75 meters 

 altitude. On trees. 



Pleurothallis falcatiloba, sp. nov. 



Herba parvula, erecta, epiphytica, circa 10 cm. alta, rhizomate valde 

 abbreviate. Radices numerosissimae, intertextae, glabrae, flexuosae. 

 Caules perbreves, unifoliati, biarticulati, vaginis binis scariosis tubularibus 

 omnino obtecti, plus minusve 1.5 cm. alti. Folia anguste oblongo-oblance- 

 olata, apice late rotundato minute bilobata et apiculata, basi angusta 

 sensim angustata, coriacea, nervo medio plus minusve supra sulcato et sub- 

 tus carinato, 5-7.1 cm. longa, 7.9 mm. lata ultra medium. Scapi folia 

 paulo excedentes, gracillimi, teretes, 7.5-8.5 cm. alti. Pedunculi ad 

 racemum vaginis perpaucis tubulatis, apice longe acuminatis valde scari- 

 osis ornati. Racemi laxiflori, circa 2.1-2.6 cm. alti (sed juniores). Brac- 

 teae inflorescentiae vaginis similibus, membranaceae, laxae, infundibuli- 

 formes, longe et acriter acuminatae. Flores pro planta grandes; sepala 

 crassiora, ut videtur subparallela. Sepala lateralia dimidio basali connata, 

 circa 11.5 mm. longa, parte apicali dorso carinata, acuminata, carina in 

 mucronem extensa. Sepalum intermedium simile, anguste lineari-lanceo- 



