A tooth of hamster was found from the fissure-filling sediments of the Akiyoshi Area. West Japan. It is the first record of fossil hamster in Japan. The material is represented by a single isolated lower third molar, which is identified with Cricetulus sp. The morphological characters of the material are fairly similar to those of Cricetulus triton (DE WINTON). The geological age of the material is thought to be the Middle Pleistocene. It is assumed that hamsters migrated into the Japanese Islands at the time when the land connection with the Continent was present and the climate might be more continental than today.

A fossil tooth of the elephant, Palaeoloxodon naumanni, was yielded from a Late Pleistocene cave deposit in Uyama-do, Atetsu Karst, in August 1967. Descriptions are given of the fossil specimen and an outline of the cave deposit. From the size and morphological features of the tooth (Ieft lower 4th molar), it is concluded that the elephant was a semi-adult.

The geology and speleology of the Inazumi-yama district, Mie-machi, Ono-gun, Oita Prefecture, are briefly described. The Inazumi Formation is composed of thick limestone and sandstone, slate and chert and is more than 650 meters in thickness. The formation is correlated with the lower Lower Permian to upper Middle Permian on the basis of fusulinan fossils in the limestone. The main part of Inazumi Cave is considered to have developed as a typical phreatic cave and ornamented by secondary formations in the wake of degression up to the accumulation of the Aso welded-tuff (ASO 4A), and since then submerged.

 Chemical components of the ground-water in and around Inazumi Cave are shown in Table 1. The relationship between calcium-magnesium and hydroger carbonate and that between sodium-potassium and silicic acid content are respectively discussed.