Asano and Nakamura (1937) described 14 cassidulinid species and subspecies found in Pliocene to Recent marine sediments of Japan. They stored these type specimens in the collection of Tohoku University. However, Asano and his colleague's collection including the cassidulinid types has not been well organized, as reported by Hasegawa (1986). During his investigation of the foraminiferal collection, Hasegawa found the holotype, paratype and hypotype specimens of the-species published in 1937. Since these specimens have not been available for later systematic works such as Nomura (1983a, b), herein we redescribe Asano and Nakamura's holotype and hypotype specimens in order to supplement Nomura's work, and revise taxonomically these species according to the modern foraminiferal systematics. Reexamination reveals that Cassidulina subglobosa parva is a synonym of Cassidulina decorata Sidebottom. Globocassidulina parva as described by Nomura (1983b) is in part synonymous with Globocassidulina canalisuturata Eade (1967) from Recent sediments off New Zealand.

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Two piston cores taken from the Ryukyu Trench slope, western margin of the North Pacific, contain a micropaleontologic record of the last 105, 000 years (covering the period from isotope Stage 5 to Stage 1) and 320, 000 years (covering the period from Stage 8 to Stage 1), respectively. Planktic foraminiferal assemblages are examined to reconstruct the past surface water conditions. The surface water during interglacial stages 5 and 7 was similar to the postglacial situation, when the studied region was dominated by warmer waters associated with the Kuroshio Current. During glacial stages 2, 3, 4, 6 and 8, the Kuroshio-related warm water was weaker; alternatively the influence of the temperate water which currently occupies the northern part of the Western North Pacific Central Water was stronger. In these glacial stages, the temperate water affected this region more intensely than it does today. However, the polar front characterized by the Oyashio Current has never attained this area during the last 320, 000 years. During stages 2, 4 and 6, the surface water was eutrophic; the primary productivity in DCM (deep chlorophyll maximum) layer was probably enhanced during stages 2 and 8. The sea surface temperature is estimated based on percentage frequency data of planktic foraminifera, using transfer function FP12-E. The estimated paleo-SST are 27-29°C for summer and 18-26°C for winter. As a result, glacial-interglacial fluctuations of the estimated SST are 1-2°C for summer and 4-5°C for winter; seasonal contrast during interglacials is similar to that of today and slightly greater during glacials. The decline of winter SST during glacial periods is believed to have been caused not only by the southward displacement of the temperate water mass, but also by the upward transporting of the cooler water from the underlying water column.

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Permineralized ovular conifer cones are common in occurrence in the Upper Yezo Group (Late Cretaceous in age) of marine origin, Hokkaido, Japan. This paper describes in detail a taxodiaceous ovular cone which is referable to those described originally by Stopes and Fujii (1910) and later by Ogura (1930) under the name of Cunninghamiostrobus yubariensis Stopes and Fujii. Unfortunately previous records did not show the ovular features in detail. However, we could study these in our well preserved specimen. Ovules (or seeds) in this specimen are three in number on each cone-scale, the only similarity between our cone and those of extant Cunninghamia. Vasculature in the cone-scale is different in the two. Comparison of the present cone with the other Cunninghamiostrobus cones and other allied cones hitherto described is also drawn in this paper.

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Inoceramus (Platyceramus) szaszi sp. nov. is established on a sample and supplementary specimens from the upper Middle Coniacian of the Ikushunbetsu valley, central Hokkaido. It resembles I. (Pl.) mantelli de Mercey, 1877 and also I. (Pl.) troegeri Noda, 1992, but is distinct from them in its fan-shaped outline, fairly constant obliquity and inconspicuous ornamentation. Statistical analyses of some selected characters also reveal significant morphological differences. On the ground of stratigraphic position and morphological resemblance, I. (Pl.) szaszi is presumed to descend from I. (Pl.) troegeri of the Lower to lower Middle Coniacian, but it is probably an offshoot without giving rise to any descendant.

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