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. I. movement of depression. The most remarkable point about this species is that insects seem to suck nectar out of minute open cells in the honeycombed surface of the labellum. The flowers are visited by various hymenopterous and dipterous insects; and the author saw the pollinia attached to the forehead of a large bee, the Xylocopa violacea.

Neotinea (Orchis) intacta.—Mr. Moggridge sent me from North Italy living specimens of this very rare British plant, which, as he informed me, is remarkable from producing seeds without the aid of insects. When insects were carefully excluded by me, almost all the flowers produced capsules. Their fertilisation follows from the pollen being extremely incoherent, so as to fall spontaneously on the stigma. Nevertheless a short nectary is present, the pollinia possess small viscid discs, and all the parts are so arranged that, if insects were to visit the flowers, the pollen-masses would almost certainly be removed and carried to another flower, but not so effectually as with most other orchids.

Serapias cordigera, an inhabitant of the South of France, has been described by Mr. Moggridge in the paper just referred to. The pollinia are attached to a single viscid disc; when first withdrawn, they are bent backwards, but soon afterwards move forwards and downwards in the usual manner. As the stigmatic cavity is narrow, the pollinia are guided into it by two guiding plates.

Nigritella angustifolia.—This Alpine species is said by Dr. H. Müller to differ from all ordinary orchids in the ovarium not being twisted; so that the labellum stands on the upper side of the flower, and insects