Twenty-five molluscan taxa were identified from three localities of the lower Middle Miocene Arakawa Formation in the Iwadono Hills area, Saitama Prefecture, central Japan. This fauna consists of two types of assemblage (protobranch-dominant and septibranch-dominant) and is inferred to represent a deep-water fauna (bathyal depths) on the basis of its taxonomic structure. Similarities in generic composition between the molluscan fauna of the Arakawa Formation and that of the bathyal zone in modern Sagami Bay suggest that the marine climate during the Arakawa deposition is comparable with that of the intermediate water of Sagami Bay. One new species, Neilonella tsukigawaensis, is described herein, and the stratigraphic relationship between the Arakawa and the overlying Goudo Formation is briefly mentioned.

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A Triassic conodont Cratognathodus multihamatus (Huckriede) from the pelagic limestone of the Taho Formation in Ehime Prefecture, Southwest Japan is newly reconstructed as an octomembrate apparatus with segminate Pa, angulate Pb, breviform digyrate M, alate Sa, breviform digyrate Sb₁, extensiform digyrate Sb₂, bifurcate bipennate Sc₁, and bipennate Sc₂ elements. Among the elements, the Pb, M, and S series were regarded as those of a septimembrate or octomembrate species Gladigondolella tethydis (Huckriede) by previous authors. Cr. multihamatus may comprise a lineage of the Gondolellidae; it occurs in the Tethyan realm and ranges from late Spathian or early Anisian to late Carnian.

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The evolutionary history of the bivalve genus Kaneharaia (Dosiniinae) is discussed. The genus Kaneharaia is restricted to the North Pacific region and contains four species : K. kaneharai (Yokoyama), K. kannoi (Masuda), K. ausiensis (llyina) and K. sp. K. ausiensis survived until the mid-Pliocene while the other three species became extinct at the end of the Miocene. In addition to these species, Dosinia mathewsonii from the upper Oligocene San Ramon Formation of California and D. whytneyi from the early middle Miocene Astoria Formation of Oregon most probably belong to the genus Kaneharaia. Kaneharaia evolved from the common ancestor with Dosinia because both genera share many common characteristics such as the subumbonal pit, the brown-coloured surface, and the finely crossed lamellar structure in the outer layer. Based on the fossil record, Kaneharaia first appeared in the northeastern Pacific during the late Oligocene and migrated westward during the early middle Miocene Climatic Optimum in the North Pacific.

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Serraia cataloniensis gen. et sp. nov. is differentiated from other pellatispiracean Foraminifera by the presence of one or more intercalary whorls of median chambers winding in the same direction as the primary whorl, and by frequent protoconchal and deureroconchal diverticula and a short spire of chambers around the deuteroconch. S. cataloniensis is described from the La Tossa Formation of the Bartonian regressive cycle of sedimentation in the Ebro Basin, Barcelona region, Spain.

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The Middle Jurassic sediments of Kutch have been known all over the world as a veritable storehouse of diverse fauna, particularly ammonites. The present investigation has brought to light a rich haul of gastropods hitherto unknown in Kutch. The present assemblage includes eleven new species belonging to nine genera. They are : Colpomphalus jumarense sp. nov.; Emarginula karuna sp. nov.; Helicacanthus chanda sp. nov.; Riselloidea tagorei sp. nov.; R. elongata sp. nov.; Onkospira kutchensis sp. nov.; Proconulus jadavpuriensis sp. nov.; Neritopsis (Neritopsis) patchamensis sp. nov.; N. (Hayamiella) sankhamala sp. nov.; Hayamia mitra sp. nov. and Globularia spathi sp. nov. The assemblage shows strong Tethyan affinity at generic level, but species display marked endemism since Kutch belongs to a distinct Indo-Madagascan Faunal Province. The present finding refines and widens the spatiotemporal distribution of these genera.

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Franz Hilgendorf (1839-1904)'s palaeontological studies on the Miocene planorbid snails of the Steinheim basin (Germany) frame his scientific work from his dissertation in 1863 to his last publication on this subject in 1901. Hilgendorf discovered that the different planorbids are not mixed in each layer, and noticed gradual transitions between different morphs of successive layers. These findings led to his hypothesis of species transmutation illustrated by his planorbid tree. This was the first phylogenetic tree reconstructed on the basis of real fossil evidence, and therewith it was the first palaeontological example of Darwin's Theory of Transmutation. Although Hilgendorf did not refer to Darwin emphatically, he can be called the first one who introduced Darwin's Theory of Transmutation into palaeontology.

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Two new permineralized magnolialean fruits derived from the Coniacian-Santonian strata of the Upper Yezo Group are described in this paper. Each fruit consists of floral head, convex receptacle and woody peduncle. Floral head consists of many conduplicate follicles with adaxial opening. Follicle is long stalked, unilocular and many seeded. Since the fruits differ from the already known ones of Magnoliales, a new genus Keraocarpon is proposed to include two new species, K. yasujii and K. masatoshii. A brief comparison of Keraocarpon to other magnolialean taxa is made. These two new species are distinguished from each other by the differences in size of various elements, number of follicles in the aggregate fruits, number of seeds per follicle, and other minor characters. The genus is characterized by aggregate fruits of many-seeded apocarpous stalked follicles on a slightly convex receptacle.

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