In the municipality of Winterswijk (Netherlands) in the clay-pit “De Vlijt” the uppermost Rupelien (Oligocene) is exposed at the moment. This Rupelien consists of a grey, very sandy clay (see sample). Also at other places this sandy clay was recognized (see map). A characteristic species of the mollusc-fauna is Natica fissurata Koenen. The other faunal elements are listed.