Five new species of Rugosa and four of Tabulata are described with two others previously known. They are from the Cyclocrinus Beds of the region north of Oslo, from the overlying Sphaeronid (Chasmops) and Mjøsa Limestone of the same region and from the Encrinite Limestone in the Gjerpen-Langesund district. All are Middle Ordovician in character. and indicate an age within the limits Climacograptus peltifer and Dicranograptus clingani zones of the standard graptolite sequence.
The Middle Ordovician of the Oslo Region, Norway. 2. Some Rugose and Tabula te Corals.