Permian foraminifers are abundantly discriminated from the limestone pebbles and matrix of the conglomerate member in the Motomura Formation of the Takakurayama Group distributed in the southern Abukuma Mountains. Based on microfacies and fossil contents, these limestone pebbles are classified into five types, denoted Types Ia, Ib, Ic, IIa and IIb. Type I pebbles contain Toriyamaia laxiseptata Kanmera, Minojapanella (M.) elongata Fujimoto and Kanuma, Chalaroschwagerina vulgaris (Schellwien), Pseudofusulina fusiformis (Schellwien), and Misellina (Brevaxina) sp., and are considered to be of Yakhtashian to early Bolorian age. Type IIa pebbles yield Yangchenia cf. iniqua Lee, Pseudodoliolina cf. ozawai Yabe and Hanzawa, and P. aff. pseudolepida (Deprat), and are surely referable to an early Murgabian age. Type IIb pebbles contain Wutuella cf. wutuensis (Kuo), Minojapanella (M.) parva Sheng, and Lantschichites? sp., and are considered to be of late Murgabian age. Colania sp., indicative of a late Murgabian age, occurs in the matrix of the conglomerate. Fusulinaceans in the Type IIb pebbles and matrix indicate a geologic age of, at least, the Motomura Formation. Judging from stratigraphic and paleontologic evidence in the Iriishikura and Kashiwadaira Formations, the Takakurayama Group, as a whole, seems to be correlated with the late Middle Permian (late Murgabian). In this paper, 19 species of foraminifers including one new genus, Quasireichelina, and four new species, Codonofusiella abukumaensis, Dunbarula planata, Quasireichelina expansa, and Neodiscus mirabilis, are described.

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We recovered well-preserved Triassic radiolarians from a thin-bedded limestone exposed at Khao Chiak, near Phatthalung, southern Thailand. This radiolarian fauna is associated with conodonts indicating a latest Spathian to earliest Anisian age and composed of families such as "Paleozoic-type" Entactiniidae, Actinommidae, spicule-type Palaeoscenidiidae, and acanthodesmid Nassellaria. We propose a new genus and four new species herein. The occurrence of the genera Entactinia Foreman and Polyentactinia Foreman is the first record from the Triassic.

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A new species of Inoceramus from the Coniacian of the Obira area, northwestern Hokkaido, is described on a population sample. The phylogenetic relationships between I. (Inoceramus) and I. (Platyceramus) are also discussed. I. (P.) troegeri sp. nov. shows a large extent of variation, with one extreme form resembling a form of I. (I.) teshioensis Nagao and Matsumoto from the upper Turonian of Japan while the other extreme is similar to the typical form of I. (P.) mantelli de Mercey from the upper Coniacian to Santonian of Japan. The two forms are linked with each other by various grades of intermediate forms within the species. This fact may imply that some species of I. (Platyceramus) were derived from I. (I.) teshioensis at or near the Turonian/Coniacian boundary. I. (P.) troegeri is also assumed to be a common or ultimate ancestor of various successive species of Inoceramus (Platyceramus) in later ages.

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A coleoid phragmocone with a rostrum was found from the Miocene Tsukiyoshi Member of the Akeyo Formation, Mizunami Group in Mizunami City, central Japan. It is identical with the holotype of Spirula mizunamiensis Tomida and Itoigawa, 1981, found from the Nataki Conglomerate Member of the Oidawara Formation, Mizunami Group. However, the present careful taxonomic examination concludes that mizunamiensis belongs to the genus Spirulirostra d'Orbigny, 1842. Therefore, Spirulirostra mizunamiensis (Tomida and Itoigawa) should be used for the Mizunami specimens. Spirulirostra mizunamiensis differs from Spirulirostra bellardii, Spirulirostra baetensi and Spirulirostrina lovisatoi, of the Miocene in Europe, and also from Amerirostra americana of the Miocene in Mexico. The Tsukiyoshi specimen was obtained in association with the autochthonous embaymental molluscan fauna of Cyclina-Vicarya assemblage from a tuffaceous sandy mudstone. This occurrence indicates that a pelagic spirulirostrid has been transported to the intertidal muddy bottom of the inner bay after post-mortem drifting from the open sea.

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