EXPLANATION OF ILLUSTRATION 
PLEUROTHALLIS oscITANS Ames. Upper part of plant 
drawn natural size. 1, side-view of a flower. 2, a 
fragment of the margin of the labellum showing 
the glandulose segments. 3, labellum, column and 
petal viewed laterally. 4, labellum flattened to 
show the outline. 5, sepaline lamina formed by 
the union of the lateral sepals. 6, dorsal sepal. 7, 
column (anther removed to disclose the trifid ros- 
tellum) and petals. 8, pollinia united by the gluti- 
nous substance of the rostellum, 9, column (anther 
in situ). 
Drawn by Blanche Ames, November 1933 
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