This paper presents the result of our study on the genus Hypoturrilites from the Mikasa district, Central Hokkaido. H. gravesianus (d'Orbigny, 1842), H. wrighti sp. nov., H. komotai (Yabe, 1904), H. yabei Collignon, 1964 and H. nodiferus (Crick, 1907) are described, giving new or revised diagnoses and comparisons with other species. As to H. komotai the ambiguities in the previous record of occurrence are cleared up. Hence, the described species are all early Cenomanian in age. Finally the systematic allocation of Hypoturrilites in the Turrilitidae is discussed.

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Sixty-seven ostracode species including those in open nomenclature are identified in thirty-six samples from the upper Miocene Kubota Formation, Higashi-Tanagura Group, distributed in Fukushima Prefecture, northeastern Japan. The lower part of the Kubota Formation yields Spinileberis sp. dominantly. In the middle to upper part of the formation, dominant species are Schizocythere kishinouyei (Kajiyama), Kotoracythere abnorma Ishizaki, Hanaiborchella triangularis (Hanai), Cytheropteron miurense Hanai, Paracytheridea neolongicaudata Ishizaki and Finmarchinella japonica (Ishizaki). Most of these species live off southwestern Japan under a subtropical to warm marine climate regime, but cryophilic and circumpolar species also occur sparsely in the middle to upper part. The ostracode assemblages indicate that the lower and the middle to upper parts of the Kubota Formation were deposited in an enclosed inner bay influenced by warm water and a warm shallow sea, respectively. Principal component analysis reveals that the influence of open sea water became strong in the upward sequence of the middle part. Analyses of ostracode faunas indicate that the Shiobara fauna from the Kubota Formation flourished in warm-water conditions.

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The genus Miosesarma Karasawa (Decapoda : Brachyura : Grapsidae) known from the Miocene of Japan is redefined. A phylogenetic analysis of 22 genera of the family Grapsidae MacLeay is provided based on 41 adult morphological characters. A single tree is produced (length=85, CI=0.565, RI=0.807, RC=0.456). The analysis supports the monophyly of the subfamilies Plagusiinae Dana, Grapsinae MacLeay and Varuninae H. Milne Edwards. The analysis suggests that the Sesarminae Dana is polyphyletic and that Cyclograpsus H. Milne Edwards, Helice De Haan, Metaplax H. Milne Edwards and Miosesarma are derived as sister taxa to varunines. The tribe Cyclograpscaea H. Milne Edwards is treated as a subfamily Cyclograpsinae (nomen. transl.) consisting of Cyclograpsus (type genus), Helice, Heterograpsus Campbell and Griffin, Metaplax, Miosesarma and Paragrapsus H. Milne Edwards, which were previously placed within the Sesarminae. within the Grapsidae, the Varuninae and Cyclograpsinae are sister groups nested as the most derived clade, followed by the Sesarminae, Grapsinae, and the most basal Plagusiinae. Five subfamilies within the Grapsidae are redefined based on the phylogenetic analysis. During a review of fossil records of the Grapsidae, 25 species, 17 genera and four subfamilies are recognized as fossils. Maingrapsus Tessier et al., Palaeograpsus Bittner, and Telphusograpsus Lorenthey, known from the European Eocene, are referred to the family Goneplacidae H. Milne Edwards and Sculptoplax Muller and Collins from the Eocene of Hungary is referred to the Xanthidae MacLeay. Fossil grapsids exhibiting the dorsal carapace only can not confidently be referred to subfamilies.

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The occurrence of an Early Campanian planktonic foraminiferal assemblage consisting of Globotruncana arca, G. linneiana, Rosita fornicata and R. patelliformis is first reported from the Upper Haborogawa Formation exposed in the Haboro area, northwestern Hokkaido, Japan. This finding supports the previous interpretation that the Santonian/Campanian boundary can be placed at the basal part of Inoceramus (Platyceramus) japonicus Zone of the inoceramid biostratigraphy.

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A Middle Permian (Murgabian) brachiopod fauna is described from the lower Moribu Formation in the Moribu area, Hida Gaien Belt, central Japan. This fauna consists of 29 species, of which 2 are new, in 27 genera. The new species are Fallaxoproductus moribuensis and Alispiriferella japonica. The Moribu fauna is a Boreal-Tethyan mixed fauna and allied with the Middle Permian brachiopod faunas of central Japan (Ise in the Hida Gaien Belt), northeast Japan (South Kitakami Belt), eastern Russia (South Primorye), northeast China (Jilin) and north China (Inner Mongolia). These regions were probably a continental shelf bordering the northeastern margin of the Sino-Korean block, which was present at a middle northern palaeolatitude in the Middle Permian time.

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An exceptionally well-preserved cephalopod mouthpart was discovered in a phosphate concretion from the lower Missourian (Upper Pennsylvanian) in Tulsa, Oklahoma, U.S.A. It consists of an almost complete jaw apparatus and a radula, both of which are in the living orientation. The black upper and lower jaws, preserved as phosphate, were probably chitinous. The lower jaw is slightly larger than the upper and is characterized by a widely open outer lamella. The upper jaw is built up of a large outer lamella and a short, scallop-shaped inner lamella; the former is distinctly divided into two portions in the posterior region. The radula is preserved in the anterior portion of the buccal cavity ; it is made of more than ten rows of teeth, each consisting of seven tooth elements with a pair of marginal plates. The overall features of the jaws and radula are essentially similar to those described in association with ammonoids rather than nautiloids and coleoids, suggesting that this mouthpart can be referred to the Ammonoidea. However, the lower jaw in our specimen differs from previously described mandibles of Carboniferous Gastrioceratoidea, Neoglyphioceratoidea, Gonioloboceratoidea, and Dimorphoceratoidea in its less elongate outline. For this reason, we refer the cephalopod mouthpart to the Ammonoidea other than the above superfamilies with reservation.

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The shell ultrastructure of nine Cretaceous rhynchonellide brachiopod genera was studied using SEM with the purpose of finding additional criteria for the taxonomy and phylogeny of Late Cretaceous rhynchonellides. The genus Orbirhynchia is characterized by a coarse fibrous basiliolidine type structure of the secondary shell. The genera Cyclothyris, Cretirhynchia, Septatoechia, Belbekella, Lamellaerhynchia, Almerarhynchia, Burrirhynchia and Grasirhynchia have a fine fibrous rhynchonellidine type structure. An outline of some diagnostic characteristics for each genus is presented. Some diagenetic alterations of the shell, such as silicification and recrystallization are also discussed.

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