July, 1922] BAILEY — POLLINATION OF MARCGRAVIA 
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nectariferous appendages of Souroubea, Marcgravia, and certain species 
of Norantea supplying a delectable beverage for birds. 
Fig. 5. Marcgravia purpurea spec. nov. A. Pedicel and flower bud. B. Pedicel and 
fruit. C. Pistil. D. Stamen. E, F. Nectariferous appendages; (a) rudimentary flower 
bud at apex of adnate pedicel. G. Abnormal appendage, showing elongated pedicel and 
flower bud. X i/i. Drawn from material preserved in formalin-alcohol by Miss Grace 
Griffin. 
Belt (1874) was the first, however, to offer any concrete suggestion 
concerning the significance of the morphological peculiarities of the highly 
specialized inflorescences of Marcgravia. The following paragraph, quoted 
from his highly entertaining book, "The Naturalist in Nicaragua," sum- 
marizes his hypothesis : 
Higher up the valley more trees were left standing and amongst these small flocks 
of other birds might often be found, one green with red head {Calliste laviniae Cass.); 
another shining green, with black head {Chlorophanes guatemalensis) ; and a third, beau- 
tiful black, blue and yellow, with a yellow head {Calliste larvata Du Bus.). These and 
many others were certain to be found where the climbing Marcgravia nepenthoides ex- 
panded its curious flowers. The flowers of this lofty climber are disposed in a circle, 
hanging downwards, like an inverted candelabrum. From the center of the circle of 
flowers is suspended a number of pitcher-like vessels which, when the flowers expand, 
in February and March, are filled with a sweetish liquid. This liquid attracts insects, 
and the insects numerous insectivorous birds, including the species I have mentioned 
and many kinds of humming-birds. The flowers are so disposed with the stamens hanging 
downwards, that the birds, to get at the pitchers, must brush against them, and thus 
convey the pollen from one plant to another. A second species of Marcgravia, that I 
found in the woods around Santo Domingo, has the pitchers placed close to the pedicels 
of the flowers, so that the birds must approach them from above; and in this species the 
flowers are turned upwards, and the pollen is brushed off by the breast of the birds. 
Belt's generalization, that the inflorescences of Marcgravia are adapta- 
