ORCHIDACEiE 



palum dorsale ovato-lanceolatum, acuminatum, 4 mm. longum, 

 1-1.5 mm. latum, apice valde incrassatum, abbreviato-caudatum, 

 conspicue trinervium, valde concavum ut videtur. Petala 2 mm. 

 longa, 1 mm. lata supra medium, spathulata, valde obtusa vel ro- 

 tundata, uninervia, in sicco pellucida. Labellum 2 mm. longum, 

 1 mm. latum, prope basim obscure rotundato-lobatum vel dila- 

 tatum, breviter unguiculatum, prope apicem leviter incrassatum, 

 obtusum, disco bicarinato, carinis usque ad 1 mm. longis, nervo 

 medio incrassato. Columna prope apicem valde bialata, alis 

 quadratis. 



Pleurothallis Williamsii is similar to P. Broadwayi Ames, but 

 is larger both in floral and in vegetative parts, and with an ob- 

 long rather than an elliptical labellum. From P. lepanthoides 

 Schltr. it differs in its smaller leaves, fewer flowered racemes, 

 and smaller sepals. 



Panama, Cana and vicinity, R. S. Williams 976^ April 17-June 8, 1908. 

 2000-6500 feet altitude. 



PLOCOGLOTTIS Bl 



Plocoglottis McGregorii Ames sp. nov. Rhizoma repens, 

 lignosum, validum. Pseudobulbi vel caules monophylli, erecti, 

 sensim in petiolum folii transeuntes, cum folio plus minusve 40 

 cm. alti, pauciarticulati, statu juvenili vaginis vestiti. Bracteae 

 vel vaginae mox in fibras persistentes solutae. Petiolus gracilis, 

 plus minusve 1 dm. longus, in sicco 2 mm. in crassitudine, pur- 

 pureo-tinctus. Folium plus minusve 3 dm. longum, utrinque at- 

 tenuatum, plus minusve 3.5 cm. latum, anguste elliptico-lanceo- 

 latum, acuminatum, acutum, prominenter trinervium, in sicco 

 viridi-flavum et albo-punctatum. Scapus lateralis, plus minusve 

 40 cm. altus, purpureo-tinctus, setulosus vel pubescens, infra 

 racemum paucibracteatus ; bracteae infimae vaginantes, elon- 



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