base, about 3.9 mm. long and 2.25 mm. wide. Lateral 
sepals more or less connate (from one half nearly to the 
apex), deeply concave, very obliquely suborbicular-ovate 
with broadly rounded outer margins and nearly straight 
inner margins, subacute to obtuse, about 8 mm. long and 
2mm. or more wide when expanded. Petals much smaller 
than the sepals, transverse, semiorbicular-ovate, broadly 
rounded and fleshy-thickened above, lightly 8-nerved, 
about 0.6 mm. long and 0.75 mm. wide. Lip slightly 
longer than the petals, suborbicular-ovate in outline, 
broadly rounded in front, obscurely 3-lobed near the base, 
broadly cuneate at the sessile base when viewed from 
above, with the basal portion membranaceous and the 
anterior part rather fleshy, about 0.87 mm. long and sub- 
equally wide across the dilated basal portion; anterior 
portion suborbicular, concave; disc with a transverse 
fleshy arching keel separating the large anterior part from 
the suborbicular basal dilation. Column minute, strongly 
dilated upward, deeply 3-lobed above. 
This species is somewhat allied to Stelis velutina 
Lindl., but the sepals are smooth within and the lip is 
differently proportioned. 
Cuzco: Prov. of Urubamba, Machupicchu, on rocks at 2100 meters 
altitude, flowers apparently yellowish, April 15, 19438, C. Vargas 38343 
(Tyrer in Herb. Ames No. 65212). 
Stelis dupliciformis C. Schweinfurth sp. nov. 
Herba mediocris, epiphytica. Rhizoma conspicuum, 
vaginis tubulatis arcte obtectum. Caules bini ut videtur, 
vaginis duabus vel tribus ornati. Folium longe petiola- 
tum; lamina lanceolato-elliptica, subacuta, infra valde 
cuneata. Racemi saepissime bini, folio breviores vel hune 
paulo excedentes, supra dense multiflori. Flores pro 
genere magni, bilabiati. Sepalum dorsale ovatum, acu- 
tum, infra quinquenervium. Sepala lateralia in laminam 
valde concavam connata, quae sepalo dorsali paulo bre- 
[15 ] 
