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36 flowers in the other spikes of O. fusca, and the proportion of pollinia removed was evidently not greater than in the two in the list. The ten spikes bore altogether 358 flowers, and, in accordance with the few pollinia removed, only eleven capsules had been formed: five of the ten spikes produced not a single capsule; two spikes had only one, and one had as many as four capsules. As corroborating what I have before said with respect to pollen being often found on the stigmas of flowers which retain their own pollinia, I may add that, of the eleven flowers which had produced capsules, five had both pollinia still within their now withered anther-cells.

From these facts the suspicion naturally arises that O. fusca is so rare a species in Britain from not being sufficiently attractive to insects, and to its not producing a sufficiency of seed. C. K. Sprengel noticed, that in Germany O. militaris (ranked by Bentham as the same species with O. fusca) is likewise imperfectly fertilised, but more perfectly than our O. fusca; for he found five old spikes bearing 138 flowers which had set thirty-one capsules; and he contrasts the state of these flowers with those of Gymnadenia conopsea, in which almost every flower produces a capsule.

An allied and curious subject remains to be discussed. The existence of a well-developed spur-like nectary seems to imply the secretion of nectar. But Sprengel, a most careful observer, thoroughly searched many flowers of O. latifolia and morio, and could never find a drop of nectar; nor could Krünitz find nectar