Abstract
The Tokiguchi and Seto Porcelain Clay Formations of the Tokai Group that are distributed in central Japan are characterized by the occurrence of Pinus trifolia Miki and many exotic, warm temperate taxa with such as the extinct genus Hemitrapa. Dr. Shigeru Miki described P. trifolia and many fossil species from the flora of these formations along with a new genus, Metasequoia. This paper reviews paleobotanical, stratigraphic, and sedimentological research of the porcelain clay formations since Miki’s work. The age of P. trifolia flora is now correlated to the latest middle Miocene to early late Miocene (10–12 Ma) based on fission track dating of the tephras.
