Trace-fossils from the lower Sakamizu Formation of the Ashiya Group (Miocene) of North Kyushu, Japan, were investigated as a part of the paleoecological study of this group. Problems concerning the taxonomy of trace-fossils are discussed briefly. Ophiomorpha ashiyaensis ichnosp. nov. and seven other tracetaxa are classified on the morphological basis and the builder organisms are considered to some extent. Furthermore, short notes on their occurrence and faunal association are given in regard to the sedimento-ecological environments. Finally, a successional bathymetric change recorded in the lower Sakamizu Formation is demonstrated.

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Four fusulinid species and one new coral species described in this article were found from the Upper Paleozoic at the south of Pampa Lobos, Chaparra area, Southwest Peru. Judging from the paleontological data, the present fossil assemblage indicates an early Wolfcampian age.

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Stratigraphy : A brief geological summary of Late Cenozoic sediments of the Oga Peninsula in northeast Japan is given as the basis of paleontological study. The Anden and Katanishi Formations are redefined and the wide distribution of the Anden Formation is indicated. Lithological and paleontological evidence indicates six cycles of sedimentation within Upper Pleistocene deposits. Each cycle consists of four units, unit-A to unit-D. Ostracoda : Individual numbers of ostracods per unit volume of sediment vary cyclically in response to lithologic changes. The occurrence of poorly preserved carapaces is confined to the uppermost and lowermost horizons of unit-C sediments. It is probable that some environmental changes might have caused decalcification of those carapaces, because EDTA treatment of well preserved carapaces produced the state of preservation similar to that observed on the poorly preserved specimens. The observed species are assumed to have belonged to shallow marine faunae because the fossil assemblages have species in common with Recent offshore ostracod communities occurring at depths of about 25m and 50m, off the Oga Peninsula. The ostracod faunae characterized by cold-water species are replaced by those containing warm-water species responding to the cyclic sequences of lithofacies and probable environmental changes, especially an increase in water temperature. The degree of mixtures of communities is discussed by comparing the structure of fossil assemblages with Recent communities and assemblages. Finally, two new species, Finmarchinella hanaii and F. nealei, are described.

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