| Summary: | The general development of Antarctic research and the reasons for the research presented in this thesis were outlined. The Antarctic region was divided into continental, maritime and sub-Antarctic areas on climatic and floral characteristics. Physical and biotic features of the maritime Antarctic were then described, particularly those on Signy Island. Features of taxonomic significance in the phylum Tardigrada were discussed, with particular reference to those of the Antarctic tardigrades. The tardigrade species recovered from the Antarctic in this study were described and illustrated. The recoveries in this investigation are compared with those of previous workers in the Antarctic region. The total Antarctic tardigrade fauna was found to number 23 species, only 11 of which had been found by two or more investigators. It was suggested that the lack of species confirmation may relate to the difficulties in identification of the Diphascon group. Only four species had not been recorded in other regions of the world, and two of these were only recently known to science. The taxonomic difficulties encountered with the Rotifera meant that only four categories were recognised: Adineta Bdelloidea, Monogononta and inactive rotifers. A total of 43 sampling sites on Signy Island were described, eight in detail since they were considered to be representative of the most common vegetation types of the Antarctic, and these were used to determine tardigrade and rotifer population densities. Tardigrades were assumed to be cylindrical with the exception of Echiniscus which was assumed to be half a prolate spheroid. Samples of mosses and lichens were collected from 70 sites in the Antarctic Peninsula and Scotia Ridge region. The microclimate at locations along the Antarctic Peninsula and Scotia Ridge region was deduced for macro-climatic data, it was then used to account for tardigrade densities and species diversity in the region. Two sites on Signy Island were chosen as being representative of two moss communities which are ...
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