and in the degree of hairiness of the inner surface of the 
sepals. According to collectors’ notes the flowers are 
transparent white with purple stripes on the sepals (P. 
Wagneri form), green with brown-purple stripes, yellow- 
green with purple stripes, brownish, red, dark red-purple 
or blackish purple. Rarely there appears in the petals a 
slight but abrupt narrowing above on each side or even 
a little tooth on one side above. Commonly the inner 
surface of the sepals appears to be distinctly pilose, but 
the hairs may be indistinct, short or lacking. 
This species extends from Guatemala and Nicaragua 
to Costa Rica and Panama. 
Other plants which form a group of puzzling allied 
species are P. Aguilar Ames, P.amethystina Ames, P. 
canae Ames, P. Johannis Schlitr., P.pompalis Ames and 
P.vinacea Ames. This group (together with P. segovien- 
sis Reichb.f.) may, with more extensive collections, be 
found to represent various extremes of one polymorphic 
species. For the present, however, these species appear 
to be clearly differentiated from P. segoviensis by mor- 
phological characters of the lip. 
Pleurothallis vaginata Schlechter in Fedde Re- 
pert. Beihefte 19 (1928) 197. 
Pleurothallis umbraticola Schlechter in Fedde Re- 
pert. 27 (1929) 56. 
A close comparison of a record of the type of the 
Costa Rican Pleurothalls vaginata with several speci- 
mens referable to that species from Costa Rica and with 
the type collection of the Bolivian P. wmbraticola con- 
vinees us that these species are conspecific. The Costa 
Rican representatives differ from P. wmbraticola chiefly 
in having more or less distinctly 8-nerved (rather than 
1-nerved) petals. The degree of acuteness of the sepals 
in these specimens appears to be a variable character. All 
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