Two new species of decapod crustacean, Hoploparia miyamotoi (Astacidea : Nephropidae) and Callianassa masanorii (Thalassinidea : Callianassidae), are described from the Upper Cretaceous lzumi Group of Osaka and Hyogo Prefectures, Japan. H. miyamotoi represents the first record for the genus from Cretaceous deposits of Japan and C. masanorii is the second of a callianassid known from the Japanese Cretaceous. The occurrence of H. miyamotoi extends the known geographic range of Hoploparia to the west side of the North Pacific.

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A total of 68 specimens of thick-shelled, peculiarly shaped Miocene mytilids from Hokkaido and northern Honshu were examined from the viewpoint of constructional morphology. They have been treated as members of three species : Mytilus (Plicatomytilus) ksakurai, M. (Tumidimytilus) tichanovitchi, and M. (T.) furanuiensis, with different shell shapes, muscle scars and surface sculpture. M. ksakurai shows an abrupt increase in shell convexity during ontogeny, like that in M. tichanovitchi. It develops a few conspicuous plications just after this allometric change in shell convexity. Polished sections of the shell of M. ksakurai reveal that just after the abrupt change in shell convexity, the internal growth increments bend sharply toward the inside of the shell. This is associated with a remarkable thickening of the outer part of the fibrous prismatic layer of the shell. These facts suggest that in M. ksakurai, the mantle tumed inward at the stage of the allometric change in shell convexity. Consequently, the diverging plications were formed by the wrinkled mantle as a result of the reduction in space across which the mantle extended.

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Two lyttoniid brachiopod species, Coscinophora magnifica Cooper and Grant, 1974 and Leptodus nobilis (Waagen, 1883) are described from the Middle and Upper Permian limestones in the Akasaka district, Mino Belt, central Japan. The Permian brachiopod fauna of Akasaka is characterized by a mixture of both Tethyan and North American elements. The fauna is considered to have occupied a mid-equatorial region of the Panthalassa Ocean in Permian time.

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Part of a right dentary of a pseudodontorn, bony-toothed bird, was newly found from the shell bed of the Kamimitsugano tuffaceous siltstone Facies of the Mitsugano Member in the Oi Formation (17.5-17 Ma), Ichishi Group in the Misato area, Mie Pref., Central Japan. This is the first record of a pseudodontorn bill from the Miocene of Japan. The discovery supplements the fossil record of pseudodontorns in Japan, which comprises the Early Oligocene to the Pliocene. The arrangement of the bony teeth corresponds to that of Osteodontornis orri Howard, 1957 known from the west coast of North America, and the specimen is provisionally identified as Osteodontornis sp.

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Twenty species of calcareous nannofossils belonging to 11 genera are identified from the Seoguipo Formation in Cheju Island, Korea. On the basis of the marker species, the Seoguipo Formation is biostratigraphically assigned to the Pseudoemiliania lacunosa Zone (NN19), which corresponds to the combined zones of Emiliania annula-Emiliania ovata (CN13a-CN14a) of the latest Pliocene and Early Pleistocene. Generally, cold-water species are dominant in the lower part, and warm-water ones in the upper part. This suggests that the paleoceanographic condition of the study area changed from a cooling to a warm phase. The change in floral composition and abundance of specific species allows recognition of four ecostratigraphic zones in the Seoguipo Formation and the migration of an oceanographic frontal boundary. According to nannofossil distribution in the study area, the position of an oceanographic boundary between warmer water and cooler water appeared to have oscillated north-south over the Korea Strait and Cheju Island in response to glacial and interglacial cycles. The geologic time of the interpreted paleoceanographical changes determined by nannofossil biochronology agrees well with the results obtained from the Japan Sea (East Sea) and Japan-Sea side of Japan.

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An exceptionally well-preserved example of Phymatoderma granulatum from continental slope deposits within the Pliocene Upper Onzole Formation, coastal Ecuador, supports an important reinterpretation of this large, branching, subhorizontal burrow system. Traces such as this have been regarded simply as fodinichnia (the work of subsurface deposit feeders). However, we propose that the trace producer was capable of changing its feeding strategy as a probable adaptation to a variable trophic regime. Tunnels within the burrow system are filled with pelleted volcanic ash conveyed from the seafloor to subsurface storage areas, indicating surface deposit feeding ; the same tunnels enclose secondary tunnels that rework the primary fill of pellets, pointing to recycling/restocking of fecal banks as another trophic behavior. Alternative feeding strategies represented in P. granulatum could be the reactions of the burrowing animal to a pulsed delivery of labile organic material at the ocean bottom (in this instance associated with large ashfalls).

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The Early Cretaceous Okurodani Formation, Tetori Group, near Shokawa village, Gifu Prefecture, Japan, has yielded a mixed assemblage of terrestrial and aquatic small vertebrates, including the fragmentary remains of a frog (ilium, vertebra) and a salamander (vertebra). These are the first Mesozoic lissamphibians recorded from Japan, and some of the oldest from Asia. The ilium is of rather primitive form and suggests a frog of basal grade, that is outside the Discoglossanura.

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Two Lochkovian (Early Devonian) species, Tractabilis? sp. and Gotlandellites fukujiensis sp. nov., from the Fukuji Formation, and an Eifelian (Middle Devonian) species, Tentaculites sp., from the Nakazato Formation, are described and comprise the first modern treatment of tentaculitids in Japan. This discovery of Gotlandellites fukujiensis extends the stratigraphic range of the genus, which was previously known from the Early Silurian.

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