Although their value as palaeoenvironmental and palaeoclimatic proxies is widely acknowledged, ostracods have traditionally been considered to be of only limited use in British Pleistocene biostrati-graphy. To some extent this is due to the patchy and fragmentary nature of most onshore Pleistocene deposits, precluding the establishment of long, continuous records on which to base species ranges. It is also a result of taxonomic continuity; the majority of British Pleistocene species are still alive today and relatively few extinct taxa, such as might provide stratigraphical markers, have been recognized. Examples of the latter were discussed by Griffiths (2001) in his review of the use of European freshwater ostracods as biostratigraphic indicators, including Scottia browniana (Jones, 1850), Ilyocy-pris quinculminata Sylvester-Bradley, 1973 and Amplocypris tonnensis Diebel & Pietrzeniuk, 1975. The presence or absence of species in any particular stratigraphical or geographical location is usually best explained, however, in terms of local environmental conditions and/or climate. This is true not only of Britain, but of the rest of the world in general. An excellent and comprehensive recent work, Holmes & Chivas’ (2002) The Ostracoda: Applications in Quaternary Research, covers palaeoceanography and palaeoenvironmen-tal analysis (including trace-element and stable-isotope techniques) in detail but has no chapter on biostratigraphy.
Perceptions of the biostratigraphical value of Pleistocene ostracods are changing. Studies carried out on ostracod assemblages from new excavations of Pleistocene sites in Britain, coupled with taxo-nomic revisions, are revealing a growing number of taxa with limited chronostratigraphic ranges. At the same time, multidisciplinary