The pioneer studies of Skottsberg (1912), supported by the observations of Bertram (1938) and Bryant (1945), showed that a range of bryophyte and lichen communities are developed in many localities along the west coast of the Antarctic Peninsula and on its offshore islands. In contrast, the terrestrial vegetation over much of the Antarctic continent is apparently restricted to sparse, widely scattered communities of lichens, with mosses playing only a subordinate role, particularly in inland areas (Siple 1938; Rudolph 1963; Greene 1964). Holdgate (1964) thus proposed a division of the Antarctic botanical zone into Maritime and Continental areas, the former having an oceanic rather than a continental climate, and supporting liverworts and two species of vascular plants in addition to well-developed moss and lichen communities. The Maritime area, which can thus be characterized in vegetational and floristic terms, has yet to be clearly defined geographically, but extends over much of the Scotia Ridge-Antarctic Peninsula sector. The present paper aims at giving a preliminary account of the vegetation in this area, based on observations made in a variety of localities from Candlemas Island south to Neny Island. The distribution of these sites is indicated in figure 17, and the extent of observations at each locality has been described elsewhere (Longton 1966 #). Because of taxonomic difficulties a detailed analysis of the vegetation in each area was impracticable, since many of the taxa can at present be named only to the generic level (Greene 1964). The major divisions of the vegetation have been defined, however, and their distribution is discussed in relation to climatic, edaphic and biotic factors, enabling an attempt to be made at outlining the geographical boundaries of the Maritime Antarctic.