The Middle Ordovician of the Oslo Region, Norway. 21. A new pelecypod of the genus Palaeosolen Hall, 1885.
A new species of Palaeosolen Hall, 1885, Palaeosolen ordovicicus, is described from the Middle Ordovician of the Oslo Region, Norway. Species of Palaeosolen have hitherto not been recorded with certainty in beds older than the Devonian.