TROPICAL AMERICAN ORCHIDS 
vulum appears to be the same as Maxillaria microphyton, 
and from the original deseription it is quite impossible to 
find substantial differentiating characters between them. 
Both of the species were collected by Tonduz under the same 
field number (9670), and it is probable that Schlechter de¬ 
scribed the same species twice under different genera, and 
that his Ornithidium parvulum is a synonym of Maxillaria 
microphylon. 
Costa Rica, Cachi, C. II. Lankester 508, 1923. Sepals 
and petals hyaline, striped with maroon. Column pale 
green. (Type in Herb. Ames No. 27219.) 
Oncidium floridanum Ames sp. nov. 
Oncidium sphacelatum Ames Contrib. Orch. FI. So. Fla. 
(1904) 22 (exclude t.), non Lindl. 
Herba terrestris, caulibus foliatis pseudobulbo bifoliato 
terminatis. Folia sub pseudobulbo pauca, plana, coriacea. 
Pseudobulbi elongati, valde complanati, ancipites, in sicco 
canaliculati. Folia ligulata, acuta. Pedunculus elongatus, 
laxe ramosus vel subsimplex. Bracteae inflorescentiae 
squamiformes, pedicello multo breviores. Sepala lateralia 
libera, elliptico-oblonga, subtus prope apicem valde sed 
breviter carinata. Sepalum dorsale simile, subtus incon- 
spicue carinatum. Petala ovato-lanceolata, subtus prope 
apicem breviter carinata, margine plus minusve undulata. 
Labellum toto ambitu panduriforme; lobi laterales parvi, 
rotundati; lobus intermedins transverse oblongus vel ob¬ 
scure reniformis, levitcr emarginatus. Crista in basi disci 
septemdentata, dentibus basilaribus lobulatis. Columna 
prope apicem utrinque alata. 
Terrestrial herb. Roots coarsely fibrous, whitish, 
spreading. Pseudobulbs congested, subtended by several 
elongated leaves which are sheathing at the base, 8-12 cm. 
long, about 2 cm. thick in greatest diameter, strongly 
flattened, ancipitous, bifoliate at the apex. Leaves ligulate, 
4 dm. or more long, 1.5-2 cm. wide, acute, coriaceous in 
texture. Peduncle stout, about 6 dm. long, terminating in a 
compound raceme, or rarely in a simple raceme. Bracts of 
the peduncle below the inflorescence closely oppressed. 
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