Abstract
In this paper four species of Coniacian ammonites are described to supplement previously published monographs (MATSUMOTO, 1965-1971). They are two new species of Peroniceras, which are allied to P. stefaninii VENZO and P. besairiei VAN HOEPEN respectively, Sornayceras cf. proteus MATSUMOTO, which is based on a large specimen, and Barroisiceras onilahyense BASSE. The localities and stratigraphic positions of the described specimens are explained at length. As an appendix, remarks are given by one of us (T. M.) on the Coniacian biostratigraphy in western Europe and other selected regions and also on the zonation and correlation of the Coniacian equivalent in Japan.
