A comparison of the characters which Cogniaux so 
carefully set forth in his description of Pleurothallis lep- 
topetala with this drawing and with the original descrip- 
tion of P. discoidea indicates that, in all essential charac- 
ters, the two concepts are identical. A study of the ample 
Trinidadian material hitherto determined as Plewrothallis 
leptopetala reveals that the lip may vary from cordate- 
ovate to triangular-ovate and from apically subacute to 
rather obtuse; the margins may be lightly sinuate or 
entire. The material examined shows little variation in 
relative sizes of floral parts. 
Cogniaux, in his description of Pleurothallis discoidea, 
characterized the dorsal sepal as twice as long as the lat- 
eral sepals. ‘This unusual characteristic is not mentioned 
in Lindley’s original description. It is not indicated by 
the drawing of the type nor by any of the specimens from 
Trinidad which I am referring to Pleurothallis discoidea. 
Trinipap: Cunupia, March 23, 1892, Alexander s.n. (Herb. Ames 
7455); Arima, July 1, 1908, Broadway s.n. (Herb. Ames 12722, 
Dupticare tyre); Base of Mt. Tamana, April 18, 1920, Britton, Brit- 
ton & Hazen, 1965 (Herb. Gray 2673); Heights of Aripo, January 
10-26, 1922, Broadway 9882 (Herb. Ames 22679); Heights of Aripo, 
April 11, 1922, Broadway s.n. (Herb. Trin. 10564); Saut d’Eau, 
December 14, 1930, Broadway 7439 (Herb. Ames 37843); Caparo, 
Broadway 2338 (Herb. Ames 107384). 
The following sterile collections are possibly referable 
to Pleurothallis discoidea. 
Arima, February 1846 (Herb. Trin. 1623); Arima woods, October 
26, 1865 (Herb. Trin. 1968); Tucuche, January 29, 1893, Hart s.n. 
(Herb. Trin. 5206); Tucure River District, June 16, 1917, Williams 
s.n. (Herb. Trin. 8780); Mt. Tamana, April 18, 1920, Freeman s.n. 
(Herb. Trin. 9031); Morne Bleu, February 7, 1922, Broadway s.n. 
(Herb. Trin. 10689); Aripo, September 25, 1924, Freeman s.n. (Herb. 
Trin. 10796); Cumaca Road, 3rd mile, December 27, 1948, Simmonds 
316 (Herb. Trin. 14239). 
Pleurothallis ovalifolia (Mocke) Reichenbach fil. in 
Walpers Ann. Bot. 6 (1861) 188. 
Stelis ovalifolia Focke in Tijdschr. Natuur. Wetensch. 
2 (1849) 202. 
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