176 Ion. Ursin: 
distinete trinervulosis, valde concavis, lateralibus angustioribus, dorso 
carinatis, usque ad ?/, connatis; petalis ovato-subquadrangulis, apice 
subtruncatis et leviter retusis, crassiuscule tricostatis, superne subtiliter 
papillosis, sepalis multo brevioribus; labello petalis aequilongo, graei- 
liter articulato, anguste ovato, obtuso, basi subtruncato, crasse tri- 
costato, margine diaphano, superne subtiliter granuloso; columna 
gracillima, petalis breviore, clinandrio hyalino, postice producto, tri- 
denticulato. 
Radices numerosissimae, dense fasciculatae, filiformes, tortuosae, 
albidae. Caules paulo flexuosi, 2—5 cm. longi, 1—1!/, mm. crassi; vaginae 
2—3, laxae, scariosae, laeves, pluricostatae, apice oblique truncatae, 1—2 cm. 
longae. Folium erectum, rigidum, limbo plano, 3— 5 cm. longo, 13— 
18 mm. lato, petiolo gracili, 5—7 mm. longo. Pedunculus communis 
erectus, subfiliformis, leviter flexuosus, teretiusculus, 10—13 cm. longus; 
spatha basilaris rigidiuscula, obtusa, dorso carinata, 8—14 mm. longa; pedi- 
celli erecti vel patuli, filiformes, subrecti, cum pedunculo breviter connati, 
cum ovario 6— 8 mm. longi. Bracteae scariosae, 4—5 mm. longae. Flores 
purpureo-fusci. Sepala 8 mm. longa, dorsale 2!/, mm. latum, lateralia 
1!/, mm. lata. Petala erecta, subplana, 3 mm. longa,‘ 2 mm. lata. La- 
bellum erectum, paulo concavum, 3 mm. longum, 1!/, mm. latum. Co- 
lumna subrecta, apice non vel vix dilatata, 2 mm. longa. 
Hab. in Sto. Domingo supra arbores in sylvis umbrosis prope 
Constanza, 1200 m. alt., m. Jul. fl.: H. von Türckheim n. 3481. 
(137°). Pleurothallis eryptantha Cogn. (n. sp., sect. Hymeno- 
danthae $ Caespitosae): minima, caespitosa, glaberrima; caulibus bre- 
vissimis, ascendentibus, filiformibus, 1-articulatis; folio minuto, coria- 
ceo, elliptico-ovato, apice subrotundato, basi subabrupte in petiolum 
longiusculum angustato, distinete marginato et superne breviter denti- 
culato-ciliato, subtus subtiliter sparseque punctato; pedunculo bre- 
vissimo, solitario, 1-floro, basi squamis pluribus majusculis tenuiter 
scariosis vestito; floribus minutissimis, in squamis basilaribus inclusis, 
segmentis hyalinis; sepalis lineari-lanceolatis, 1-nerviis, lateralibus 
fere usqüe ad apicem connatis; petalis anguste lineari-subspathulatis, 
acutissimis, 1-nervulosis, integerrimis, sepalis multo brevioribus; 
labello sepalis paulo breviore, angustissime breviterque unguiculato, 
anguste lineari-ligulato, basi truncato, subtiliter trinervuloso; columna 
petalis paulo longiore, gracili, apice incrassata, clinandrio margine 
subtiliter denticulato. | 
Caules recti vel paulo arcuati, 1—3 mm. longi. Folium erectum, 
rigidum, utrinque saepius purpureo-violaceum, limbo plus minusve concaVvo, 
6-9 mm. longo, 3—5 mm. lato, petiolo subfiliformi, 1—3 mm. longo. Pe- 
dunculus capillaris, 1—1!/, mm. longus. Flores erecti, purpureo-fuscl. 
Sepala satis concava, eirciter 21/, mm. longa, dorsale ?/, mm. latum, late- 
ralia in valvam 1 mm. latam connata. Petala paulo obliqua, inferne longe 
