The terrestrial molluscan fauna of some woodlands in north east Yorkshire, England

Terrestrial molluscan faunas are described from 17 deciduous woodlands in the north east of England. In total, 51 species were recorded (Mean number per site 29-06+149 range 19 to 39) some of which are nationally scarce. The woodlands fall into two groups, the more easterly ones tending to be more species rich than those in the west. Species richness is positively associated with woodland area, moisture level and age. The species contributing to these associations are considered. Comparisons are made with other studies of woodland molluscan assemblages carried out elsewhere in Britain.