1979 Volume 1979 Issue 113 Pages 30-44_1
This is the first description of Lewesiceras and Nowakites from the Cretaceous of Hokkaido. It comprises four new species which are allied to L. rhodanicum (ROMAN and MAZELAN), L. elmii COLLIGNON, N. lemarchandi (DE GROSSOUVRE) and N. tallavignesi (D'ORBIGNY), respectively. The reasons why these two genera are rare in Hokkaido are discussed in connexion with the evolutionary history of the family.