Page:Darwin - The various contrivances by which orchids are fertilized by insects (1877).djvu/243

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Chap. VII.
CYCNOCHES VENTRICOSUM.
223

the extremity of the column, or whether they first alight on this part of the column; but in either case they would cause the ejection of the pollinia, which would adhere to some part of their bodies.

The specimens which I examined were certainly


Fig. 34.

Diagrammatic Section of a Flower-bud, the column placed upright.

pd.a. anther.
pd.f. filament of anther.
pd.p. pollen-mass.
pd. pedicel of pollinium, barely separated as yet from the rostellum.
pd.d. disc of pollinium with the dependent curtain.
pd.s. stigmatic chamber.
pd.g. stigmatic canal leading to the ovarium.


male plants, for the pollinia were well developed. The stigmatic cavity was lined with a thick layer of pulpy matter which was not adhesive. But as the flowers cannot possibly be fertilised until the pollinia have been ejected, together with the great curtain which covers the whole stigmatic surface, it may be that