This section is from the book "British Wild Flowers - In Their Natural Haunts Vol5-6", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
As might naturally be expected in the case of habitats so essentially moist as bogs and marshes, insects that get their livelihood in the imago stage are not conspicuously abundant. None the less many bog- and marsh-plants rely upon insect agency for effective crossing.
Such are Great Spearwort, Marsh Marigold, Grass of Parnassus, the Sundew, Water Drop-wort, Valerian, Cranberry, Rosemary, Water Violet, Bog Bean, Bog Speedwell, Marsh Red Rattle, Bladderwort, Butterwort, Marsh Helle-borine, Bog Asphodel; the Bog Pimpernel, which grows almost covered up by other plants, making it difficult to discover it, is normally self-pollinated.
Golden Dock and Bog Myrtle are pollinated by the agency of the wind, as are all the Rush, Sedge, and Grass types that occur.