Oncidium guatemalense and Odontoglossum oliganthum 
have in the past been considered as distinct. However, 
we now consider them to be identical and referable to 
Oneidium guatemalense. 
This species is rare in Mexico and Guatemala where 
it occurs as an epiphyte on trees in forests up to 2000 
meters altitude. 
Oncidium Wentworthianum Bateman ev Lindley 
var. tenue (Lind/.) Ames & Correll comb. nov. 
Oneidium tenue Lindley in Journ. Hort. Soc. 3 (1848) 
76, fig. 
Variety tenue differs from the typical form of the spe- 
cies mainly in the usually smaller and differently colored 
flowers. The strongly undulate sepals and petals have an 
acute-apiculate apex and are commonly shorter and nar- 
rower than in typical O. Wentworthianum. They are solid- 
ly reddish brown with the apical fourth yellow, whereas 
the sepals and petals of the typical form are lemon-yellow 
with dark brown irregular blotches or stains on the lower 
half. The lip of var. terue is adorned with a wide solid 
wine-colored band across the broad isthmus. The callus 
of the lip and the column-wings are essentially alike in 
the two concepts. The inflorescence of var. tenue is oc- 
‘asionally as much as three meters in length and the 
branches are usually short and few-flowered. The floral 
measurements are as follows: Sepals 1.1-1.5 cm. long, 
3.5-6 mm. wide; petals 1-1.3 cm. long, 4-6 mm. wide; 
lip 1.3-1.8 em. long, 1.1-1.4cm. wide across the auricu- 
liform lateral lobes, 9-11 mm. wide across the bilobulate 
mid-lobe. 
There is little doubt that this variety has been confused 
with O. ansiferum Reichb.f. and other species in the O. 
reflewum Lindl. complex. Lt is easily distinguished from 
O. ansiferum by the differently shaped callus of the lip 
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