ly sigmoid auricles about 1.8 mm. long, furnished inside 
at the base with a large tuberculate ovoid callus (the calli 
of the parallel auricles contiguous). Column short, stout, 
dorso-ventrally complanate, about 1.5 mm. long. 
Pleurothalhs aurita is allied to P. concaviflora C. 
Schweinf., but is dissimilar in having shorter blunter se- 
pals, spatulate-oblong petals and lip with a pair of long 
basal auricles. It differs from P.saccatilabia C.Schweint. 
in its much smaller petals and elongate basal auricles of 
the lip. 
Cosra Rica: vicinity of El General, Province of San José, at 1100 
meters altitude, flowers yellow, November 1936, Alexander F. Skutch 
2941 (Tyrer in Herb. Ames 55415). 
Pleurothallis Broadwayi Ames Orch. 2 (1908) 
267. 
Pleurothallis guadalupensis Cogniaux in Urban 
Symb. Antill. 6 (1909) 432. 
Pleurothallis Williamsii Ames Orch. 7 (1922) 120. 
Pleurothallis guadalupensis, of which we have a speci- 
men of the type number, seems to be inseparable from P. 
Broadway. In the latter species, the stems were claimed 
by Cogniaux (l.c. p. 897) to be monophyllous; but the 
type collection in the Ames Herbarium, while commonly 
showing monophyllous stems, often bears two or three 
leaves on a single stem. On the other hand, P. guadalu- 
pensis is claimed to have two or three leaves on a stem 
but is said to be rarely monophyllous (as in our examples 
of the type collection). Moreover, the shape of the leaves 
in the two species is practically identical and there ap- 
pears to be no noteworthy difference in the floral parts of 
the two concepts. In particular the lip of P. Broadwayi, 
which is described as trilamellate, is in reality strongly 
3-nerved with only two conspicuous keels, as in P. guad- 
alupensis. In outline also the lip of P. Broadwayi might 
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