Upper Ordovician ostracods from the Oslo Region, Norway

22 paleocop ostracods are described from the Upper Ordovioian of the Oslo Region in Norway. A chart shows their stratigraphical and geographical distribution (p. 101). The following species are new: Bolbina tuberculata, Opiliium porkuniensis, Prirnitia osloensis, Platybolbina tiara, Laccochilina tarda, Bollia accentuata, Pseudulrichia norver;ica, and M oncceratella bos. The Calcareous Sandstone (5b) is included in the Ordovician, and is placed together with the Gastropod Limestone (Sa) in a new division of the U pr:er Ordovician of the Oslo Eegion, called the Dalmanitina Series. The underlying Tretaspis Series is restrictecl to 4c and 4cl . .i\Iany of the ostracocls of the Dalmanitina Series were first clescribed from glacial drift boulclers in ..'\. Germany. The fauna resembles that of the SweJish Leptaena Limestone and of the Esthonian Porkuni (Borkholm) Limestone. So;:Le of the drift spe�ies are recorclecl for the first time from in situ material.