Studies in Salt Marsh Ecology with Special Reference to the Genus Limonium

world usage. The present paper is concerned with the role of Limonium spp. in the salt marsh community rather than with the relative status of the ecological subunits. The selection of sites for detailed study was based on the presence or likely occurrence of Limonium spp. and excludes the earliest communities of the salt marsh succession. For the purposes of this study 'salt marsh' is taken to mean vegetated intertidal sites with poorly drained soils. The nomenclature follows that of Clapham, Tutin & Warburg (1962). Three species of Limonium occur in the salt marshes of the British Isles. L. vulgare is the commonest, and it occurs in suitable habitats all round the coasts of England and Wales, although it is absent from the extreme south-west of England. In Scotland it is confined to the south-west, apart from an isolated occurrence on the Firth of Forth. It is absent from Ireland. L. humile occurs all round the coasts of Ireland as well as Great Britain, where it is less common than L. vulgare. The comparative biology of these two species has already been described (Boorman 1967). Other British speces of Limonium