CENTRAL AMERICAN ORCHIDS 
Coban, H. v. Tuerckheim 3997, November 1912. 1550 
meters altitude. 
Pleurothallis arietina Ames sp. nov. Radices graciles, 
fibratae. Caules secundarii valde elongati, conspicue alati, 
paucivaginati. Vaginae caulis elongatae, arete appressae. 
Folium lanceolatum, acutum, coriaceum. Flores fasciculati, 
quam folium multo breviores, e spatha complanata orientes. 
Sepala lateralia usque ad apicem cohaerentia, laminam con- 
caviusculam oblongam formantia. Sepalum dorsale simile. 
Petala unguiculata, supra unguem oblonga, triquetra, ob- 
tusa, valde incrassata, minute et breviter glandulosa. 
Labellum unguiculatum, explanatum triangulari-crescenti- 
forme, longe auriculatum auriculis porrectis, antice valde 
incrassatum, glandulosum. Discus callo transverse in 
basi et carina incrassata in medio. Columna elongata, 
antice prope basim callo instructa, usque ad apicem minute 
glandulosa. 
Roots fibrous. Secondary stems 20-25 cm. long, 
conspicuously alate, provided above with two elongated 
closely oppressed cylindrical sheaths, one near the middle 
of the stem, the other basal, monophyllous. Leaf up to 
8.5 cm. long, 3.5 cm. wide below the middle, lanceolate, 
rounded at base, acuminate, acute, coriaceous, longer than 
the inflorescence. Flowers fasciculate in the axil of the leaf, 
the pedicels arising from a complanate sheath. Flower- 
stalks about 3 cm. long, slender, subfiliform. Lateral 
sepals 9 mm. long, united to the tip, forming a more or less 
fleshy, oblong, navicular lamina which is about 3 mm. wide 
when spread out. Dorsal sepal 8 mm. long, similar to the 
lamina formed by the lateral sepals, 3-nerved, the nerves 
prominent. Petals 8 mm. long, 1 mm. wide, unguiculate, 
oblong above the claw and triquetrous-thickened, subacute, 
minutely glandular. Labellum suggesting a ram’s head 
when spread out, about 2 mm. long to the base of the slender 
claw, triangular-crescentiform when the lateral lobes which 
are normally porrect are spread out, acute, 2 mm. wide in 
front of the basal porrect auricles which are 1 mm. long and 
narrowly triangular-acute, apical third of the labellum 
16 
