Abstract
This is Part 2 of a monograph of the Cretaceous Nautiloids from Hokkaido being published in series. It contains the description of three species, of which the first is new and assigned to Kummeloceras (established in Part 1), the second is identified with Cymatoceras pseudoatlas (Yabe et Shimizu), originally described on a specimen from Kyushu, and the last is a new species of Cymatoceras allied to and possibly evolved from C. saussureanum (Pictet) of an earlier age. The first two occur in the Lower Santonian Zone of Inoceramus amakusensis and the last in the Middle Campanian Zone of Sphenoceramus schmidti and seems to range down to the Lower Campanian Zone of Sphenoceramus orientalis. Some remarks are given on the Cymatoceratidae, proposing a new genus.
