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. IV. emitting, whilst still within the anther-cells, their tubes, which penetrate the stigma; and this occurs even in the bud. This species, however, is probably visited by insects, and occasionally crossed; for the labellum contains nectar. E. microphylla is intermediate in structure between E. latifolia, which is always fertilised by the aid of insects, and E. viridiflora, which does not necessarily require any such aid. The whole of this memoir by Dr. H. Müller deserves to be attentively studied.

Epipogium gmelini.—This plant, which has only once been found in Great Britain, has been fully described by Dr. Rohrbach in a special memoir. The structure and manner of fertilisation is in many respects like that of Epipactis, to which genus the author believes the present one to be allied, though placed by Lindley amongst the Arethuseæ. Rohrbach saw the flowers visited by Bomhus lucorum, but it appears that only a few produce capsules.

Goodyera repens. —This genus is rather closely related to Epipactis, in most of the characters with which we are concerned. The shield-like rostellum is almost square, and projects beyond the stigma; it is supported on each side by sloping sides rising from the upper edge of the stigma, in nearly the same manner as we shall presently see in Spiranthes. The surface of the protuberant part of the rostellum is rough, and when dry can be seen to be formed of cells; it is delicate, and, when slightly pricked, a little milky viscid fluid exudes; it is lined by a layer of very adhesive matter, which quickly sets hard when exposed