Page:On the Various Contrivances by Which British and Foreign Orchids are Fertilised by Insects, and on the Good Effects of Intercrossing.djvu/27

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again move downward, but, at the same time, converge. A poet might imagine, that whilst the pollinia are borne from flower to flower through the air, adhering to a moth's body, they voluntarily and eagerly place themselves, in each case, in that exact position in which alone they can hope to gain their wish and perpetuate their race.


CHAPTER III.

Epipactis palustris; curious shape of the labellum and its apparent importance in the fructification of the flower—Cephalanthera grandiflora; rostellum aborted; early penetration of the pollen-tubes; case of imperfect self-fertilisation; fertilisation aided by insect—Goodyera repens—Spiranthes autumnalis; perfect adaptation by which the pollen of a younger flower is carried to the stigma of an older flower on another plant.

WE now come to another great tribe of British Orchids, the Neottee, which have a free anther standing behind the stigma: their pollen-grains are tied together by fine elastic threads, which partially cohere and project at the upper end of the pollen-mass, and are attached (with some exceptions) to the back of the rostellum. Consequently the pollen-masses have no true and distinct caudicles. In one genus alone (Goodyera) the pollen-grains are collected into packets as in Orchis. Epipactis and Goodyera agree pretty closely in their manner of fertilisation with the Ophrea, but are more simply organized: Spiranthes comes under the same category, but in some respects is differently modified. Cephalanthera seems to be a degraded or simplified Epipactis; as it does not possess a rostellum—that eminently characteristic organ—and as its pollen-grains are single, it bears almost the same sort of relation to other Orchids, which a wingless bird does to other birds.