Spatial arrangement of various enamel types (schmelzmuster) present in the incisors and molars of some fossil and extant murid rodents of India was studied from both the functional and phylogenetic points of view. Hunter-schreger bands (HSBs) along with radial enamel (RE) in mice molars have been found to occupy the entire height of the enamel crown (from the base to the top) on the anterior and the posterior portions. These HSBs tend to be horizontal around the base and inclined apically around the top. A clear distinction between the leading and the trailing edges of chewing surfaces based on the difference in the orientation of prisms has been observed in hypsodont murid molars. On the leading edges, the long axes of prisms originating from the enamel-dentine junction tend to be oriented towards the load, whereas those on the trailing edges turn away from the load. The schmelzmuster in molars of Mus, indicate an omnivorous diet, whereas that in Golunda, Millardia, and Bandicota points to adaptation for an abrasive diet. The Indian bandicoot rat (Bandicota) with its large, hypsodont molars has developed horizontally oriented (relative to the occlusal surface) HSBs at the base of the enamel crown. These HSBs have been found in enamel layers oriented both almost parallel and perpendicular to the occlusal surface, an observation that corroborates the presence of horizontal tension at the base of the tooth due to vertical load on the occlusal surface. In the light of the observations made here, a model depicting changes in schmelzmuster in murid rodents through Late Miocene and Plio-Pleistocene times is suggested.

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The basal part of the Tanami Formation, in the southern part of the Kii Peninsula, southwest Honshu, southern Japan. These include Malletia poronaica (Yokoyama), Portlandia (Portlandella) watasei (Kanehara), and Trominina hokkaidoensis (Hayasaka and Uozumi). The combination of late Eocene to early Oligocene Asagai-Poronai mollusks and previously known Oligocene to early Miocene mollusks from the Tanami Formation implies that the localities discussed here are of Oligocene age. The presence of Trominina, which was widespread in the northern Pacific during Paleogene time, suggests that it migrated from northern Japan and northward to southern Japan, in accordance with the Eocene-Oligocene transition global cooling trend.

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Eighty-five fossil and Recent species of the genus Loxoconcha (Crustacea : Ostracoda) from East Asia are systematically reexamined. On the basis of carapace morphology, the genus Loxoconcha from East Asia is divided into five species groups : L. pulchra, L. optima, L. japonica, L. uranouchiensis and L. japonica species groups. The migration and speciation patterns of four species of the L. japonica species group are as follows. In Late Miocene, L. lilljeborgii and L. tumulosa were distributed over the Paleo-Indian Ocean. In Early Pliocene time, these species migrated to the Western Pacific and L. japonica evolved from populations of L. tumulosa by peramorphic evolution. In the Middle Pleistocene, L. shanhaiensis evolved from populations of L. japonica in the Ryukyu Islands by paedomorphic evolution.

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A small brachiopod fauna is described from the lower part of the Xiujimqinqi Formation of the Xiujimqinqi area in central-east Inner Mongolia, northeast China. The age of this fauna is regarded as Wordian (Middle Guadalupian, Middle Permian) by comparison with a similar brachiopod fauna from the Zhesi area of central Inner Mongolia, and by constraints from fusulinaceans associated with the Zhesi fauna. The Xiujimqinqi fauna is typical of mixed Boreal/Palaeoequatorial Middle Permian brachiopod faunas of East Asia. The mixed nature of these faunas is interpreted to have resulted from the combined effects of a middle palaeolatitudinal position, intensified plate convergence between Sino-Korea and Mongolia, and sea surface current connections with both the Arctic Sea in the north and eastern Palaeo-Tethys to the south. Possible Kaninospirifer is reported for the first time from China.

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A new micromorphic rhynchonellide brachiopod Parasphenarina cavernicola gen. et sp. nov. is described from submarine caves on the outer slopes of coral reefs in the ryukyu Islands, Japan. Based on the presence of spinuliform crura, the new genus is included in the Family Frieleiidae Cooper, the diagnosis of which is emended. Detailed morphological observations of different-sized shells and intraspecific variability have shown that the morphology of the hinge plates changes considerably during ontogeny. It is suggested that the new genus Parasphenarina could have evolved from forms close to the extremely rare bathyal Pliocene genus Sphenarina Cooper. The diagnostic characteristics of Parasphenarina such as diminutive adult size and lack of septalium and median septum may represent paedomorphic evolution.

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Krasnoyarichthys jesseni gen. et sp. nov. is described from the Upper Devonian (Famennian) of Western Siberia. It is the first finding of a Devonian actinopterygian in Siberia. This new genus is closely related to Moythomasia, Mimia and Kentuckia, but differs from those genera in the relative position of the fins, longer pelvic fin base and other dermal roof bones and scales characters in combination. The family Moythomasiidae with the above-mentioned genera and possibly Orvikuina is re-diagnosed and compared.

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