Thirty-five ostracod species belonging to 18 genera are recognized from the Middle Miocene Fujina Formation (ca. 14-12 Ma), 3km southwest of Matsue City, Shimane Prefecture, Japan. Most of these species are part of the recent Japan Sea proper water fauna; they are also classified into 4 categories, circumpolar, cryophilic, endemic cool-temperate and temperate species. These ostracod assemblages indicate that the Fujina Formation was deposited under a cold-water environment. Ten new species, Ambtonia shimanensis, A. takayasui, Acanthocythereis fujinaensis, A. izumoensis, Cluthia tamayuensis, C. subjaponica, Kotoracythere tsukagoshii, Laperousecythere ikeyai, Palmoconcha irizukii, and Robertsonites yatsukanus are described.

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A well-preserved palynoflora is reported from within a cored interval of a coal-exploratory borehole (1-UN-23-PI of the Geological Survey of Brazil) in the southern part of the Parnaiba Basin, northeastern Brazil. The sample studied is from the lower portion of the Piaui Formation. Its palynoflora is characterized by particular abundance of the trilete cavate/pseudosaccate miospores Spelaeotriletes triangulus Neves and Owens, 1966 and S. arenaceus Neves and Owens, 1966, together with cingulizonate forms mainly attributable to Vallatisporites Hacquebard, 1957 and Cristatisporites R. Potonie and Kremp emend. Butterworth et al., 1964. Radially and bilaterally symmetrical monosaccate pollen grains are also well-represented, chiefly by Plicatipollenites Lele, 1964 and Potonieisporites Bhardwaj, 1954, respectively. Taeniate grains (i.e., monosaccates and bisaccates) are relatively minor constituents of the palynoflora; no marine microplankton were encountered. Several species are described in detail : the trilete apiculate spores Brevitriletes levis (Balme and Hennelly) Bharadwaj and Srivastava, 1969 and Horriditriletes uruguaiensis (Marques-Toigo) Archangelsky and Gamerro, 1979; and the taeniate pollen grains Meristocorpus ostentus sp. nov. and Lahirites segmentatus sp. nov. A Pennsylvanian (Late Carboniferous : late Westphalian) age is adduced for the palynoflora via its correlation with part of the Tapajos Group (specifically, the upper Itaituba Formation) of the Amazonas Basin in northern Brazil. The entirely land-derived palynomorphs, associated with abundant plant debris, corroborate previous suggestions that the lower part of the Piaui Formation accumulated in a nonmarine setting under conditions of aridity.

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A recent collection of more than a hundred fossil bones belonging to at least six individuals of metoposaurids from the basal part of the Late Triassic, Maleri Formation of the Pranhita-Godavari valley, Gondwana succession, has helped to formulate new ideas. Detailed morphological studies have been used to include all specimens of metoposaurids so far collected from India within a single taxon, Buettneria maleriensis, a new combination. A reconstruction of the skeleton of Buettneria maleriensis is presented for the first time. Buettneria maleriensis remains are common in the continental red beds of India, deposited under fluvial conditions witnessing seasonal climate changes. While some bones of Buettneria maleriensis were rolled and transported after death and are now found as sporadic fossils in mudstone (or occasionally in sandstones and calcirudites), the other type of occurrences, the rich accumulation of bones, are present only in mudstones. Buettneria maleriensis was replaced by the Chigutisauridae, a temnospondyl family exclusive to Gondwanaland. India is the only place where both metoposaurids and chigutisaurids are found in such close succession. The paleoposition of India during the later part of the Triassic may have been responsible for this.

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Three bivalve species collected from the Permian H. S. Lee Formation at the H. S. Lee No.8 Mine in Perak, Malaysia are described. They are identified as Sanguinolites ishii sp. nov., Megalodon (Megalodon) yanceyi sp. nov., and Myalina (Myalina) cf. wyomingensis (Lea). The fossil locality is famous for the abundant occurrence of gastropods together with bivalves, cephalopods, calcareous algae and others, but is flooded and inaccessible now. The new species of Megalodon is considered to be the first record of the genus in the Permian.

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The high level systematic position and autecology of the Upper Ordovician cavity-dwelling trilobite Ityophorus undulatus is discussed. The lectotype is here selected from syntypes. The Late Cambrian family Loganellidae Rasetti, 1959 appears to contain the ancestors of this species. Ityophorus is compared with the closely related Middle Ordovician trilobite Frognaspis to pick out the stable characters. These are the yoked free cheeks, the wide cephalic doublure in combination with a distinct narrow cephalic rim, pygidial pleural and interpleural furrows, and a smooth mesial part of the inner cephalic doublural margin (lack of an embayment of the hypostomal suture). Because of the presence of several characteristics unique to the two, they are best attributed to a subfamily Ityophorinae, which is interpreted as a relict group of the Loganellidae. The discussion of the autecology is based on the structural relationship of the mouth opening and position of basal podomeres in relation to the cephalic margin, and on the functional morphology of terrace lines on the brim margin. The appendages appear to have been long to reach the substrate. The cephalon appears to have held the body rigidly by means of the terrace lines. This made it possible for the animal to use its appendages freely, for instance, in scratching the substrate. Some cavities in the present study area show evidence of a gel-like consistency of the cavity walls, which best fits the behavior mentioned above. Ityophorus is interpreted to have been an animal adapted to cavities rich in bacterial mats, on which it may have fed.

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At least 106 species were identified from 36 samples obtained from two cores (T1 and T2), which were recovered from the Kitan Strait off Wakayama City, southwestern Japan. Q-mode cluster analysis of cores T1 and T2 revealed three biofacies (PL, PT and LS). Changes in depositional environments based on the observed distribution of ostracodes were analysed, and the following sequence is proposed. Before ca. 7, 000 cal yr BP, the T1 site was a sandy coast, ranging from an outer bay to the open sea, close to a river mouth, at water depths of more than 15-20m, while the T2 site ranged from a bay coast to an outer bay, close to a river mouth, at water depths of less than 15-20m. During ca. 7, 000-2, 000 cal yr BP, the position of the sites fell within ranging an outer bay to the open sea at water depths of 30-40m influenced by residual and/or tidal currents from the straits. After ca. 2, 000 cal yr BP, the sites were situated on a sandy coast, ranging from an outer bay to the open sea, close to a river mouth, at water depths of more than 15-20m. Two new species, Trachyleberis ishizakii and Cytheropteron kumaii, are also described.

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The Paleogene Ashiya Group, in which molluscan fossils are abundant (=Ashiya fauna), consists mainly of shallow marine deposits that exhibit sedimentary cycles especially in the Waita Formation (upper part of the Group). Each cycle is redefined as a thin transgressive basal sandstone (transgressive systems tract) overlain by a progradational coarsening-upward interval (highstand systems tract). The depositional environment varies from a shallower condition influenced by strong wave action (shoreface?) to a deeper condition below the storm wave base, which is followed by next shallower conditions such as lower shoreface or intertidal zone. Molluscan fossils occur only from the thin lower part of each cycle, namely the transgressive basal sandstone and from the mudstone of the earliest progradational phase. The fossils occur both as shell concentrations and more dispersed fossiliferous deposits. Bed-by-bed sampling based on taphonomic, sedimentologic and paleoecologic observations distinguishes four fossil assemblages, (a) Glycymeris-Phacosoma, (b) Venericardia-Crassatella, (c) Venericardia and (d) Yoldia-Nucula. These assemblages occur successively in each cycle, and their taphonomic features also change upward from a wave-generated allochthonous shellbed on the basal ravinement surface to autochthonous shell patches. The successive change accompanies a decreasing wave-influence during a transgressive period. Epibionts, such as epifaunal byssally attached bivalves and barnacles, occur abundantly as associated species of the Venericardia-Crassatella assemblage from the middle part of the transgressive basal sandstone. Epibiontic colonization probably reflects taphonomic feedback, with shelly substrates avoiding burial by the winnowing of sediments during transgression. Autochthonous shellbeds dominated by Venericardia subnipponica are intercalated in the glauconitic sandstone beds (surface of maximum transgression) at the top of the transgressive basal sandstone. The shellbeds probably represent an attritional accumulation with dead shells of Venericardia supplied continuously in situ during a phase of low sediment supply.

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