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The data presented by HÄNGGI et al. (1995) and BOLAÑOS (2003) on the habitats of a large number of European spiders are examined, most of which appear to show non-specific preferences. The abundance and frequency peaks of the 384 species graphs (HÄNGGI et al. 1995) can be explained by assuming that habitat tolerance varies with geographical location. This can be demonstrated on a local level within a particular country or throughout the European range of a species. Examples are described. Many published ecological studies of spider faunas seem to have assumed that the habitat preferences of a species is a fixed characteristic wherever they occur but evidence is presented to show that this may apply to only a few species. A number of examples are described showing how preferences change with latitude and longitude within Europe. It is proposed that most species can be categorised as stenotopic, mesotopic or eurytopic, although there is a gradual change from one group to another, with no clear boundaries. Supporting evidence for regional variation in habitat tolerance is scarce. More studies are required of individual species throughout their European distribution and detailed descriptions of their habitats in different parts of their range. Definitions of micro-, macro- and minor habitats are presented as useful tools for field studies of spider faunas. It is also recommended that future faunal surveys should use the same system of habitat classification so that the results are comparable with other studies. The most appropriate method is described by BUCHAR & RŮŽIČKA (2002) but could be made more precise by the use of scientific measuring equipment for light/shade, dryness/humidity and temperature. Finally the importance of checking the validity of some published records is stressed because misidentifications are sometimes frequent.