Current issues on the systematics of Japanese stegodonts, stegolophodonts, paleoloxodonts mammoths and gomphotheres are reviewed. Phylogenetic hypothesis of the genus Stegodon should be revised based on the study of additional cranial materials which were not used by Saegusa (1987). Comprehensive study on the new materials of primitive stegodonts and stegolophodonts from southern Asia is currently underway in conjunction with the revision of the Japanese stegolophodonts. Cranial materials of Elephas recki recently excavated from Ethiopia provide new insight on the phylogeny of Eurasian Palaeoloxon. E. naumanni can be considered as a relict of once wide spread Palaeoloxodon species represented by a skull from Stuttgart. The external naris of Gomphotherium annectens has been described as narrow by Tassy (1994), but the skull of G. annectens should be re-described pending the repair of the skull. Recent finding of highly derived Sinomastodon from Thailand appears to support the idea that this genus is a sistergroup of New World gomphotheres. However, the idea should be tested by a phylogenetic analysis accompanied with a revision of the New World gomphotheres.

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 The posterior part of a skull of Stegodon miensis, which was found from Nakajo-mura, Kamininochi-gun, Nagano Prefecture, central Japan in 1970, was prepared for the first time for this morphological study. This revealed canals for nerves and vessels on the inferior and posterior surface of the skull. Comparison of the previously prepared anterior part and this posterior part with skulls of Elephas maximus revealed morphological differences. These differences can be explained by the level of antero-posterior abbreviation of the skull and differences of molar morphology and mode of molar eruption.

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 The two lophodont teeth are collected from the river beds of Tama River in Fussa, west part of Tokyo. They were found from the Upper Part of Kasumi Gravel Bed, which date to the Late Pliocene.
The features of specimens are as follows:
(1) enamel thickness is thick in wide range,
(2) various enamel foldings from small to large wave pattern;
(3) size of mammillae are in various range; and
(4) ridge frequencies higher in the Stegodon miensis compared to the S. aurorae.
However, these characters are not similar to the feature of S. miensis and S. aurorae, which were identified as the intermediate form between S. miensis and S. aurorae. The intermediate form tooth of Stegodon is the first finds from the Kazusa group and the corresponding stratum. These specimens do not indicate any trace of evolutionally stages from S. miensis to S. aurorae. Therefore, this intermediate form is very difficult to identify in the species as a result of this study based on the tooth characteristics. The Late Pliocene is known for the stage of the global coldness, which may be the reason for the evolution of the S. aurorae.

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 Naumann’s Elephant (Palaeoloxodon naumanni) is the Proboscidea fossil that best represents Japan and has been discovered at many localities all over the Japanese islands resulting in many studies. However, previous studies did not research the process of how Palaeoloxodon naumanni first reached the Japanese archipelago, subsequently expanded its distribution and finally became extinct.
 This paper studies the previous and future problems of Palaeoloxodon naumanni covering morphology, distribution, migration, phylogeny and extinction. Palaeoloxodon naumanni first occurred in MIS 10 and lasted until MIS 2. The number of fossil localities of P. naumanni is three (3.2%) in MIS 10 to 9, six (6.5%) in MIS 8, 12 (11.8%) in MIS 7, seven (7.5%) in MIS 6, 44 (52.7%) in MIS 5 and 17 (18.2%) in MIS 3 to 2. Palaeoloxodon naumanni first appeared in the Japanese archipelago just before or in MIS 10, and expanded its distribution during MIS 7. Its peak occurred in MIS 5 when the species was distributed all over the islands.
 The last P. naumanni disappeared during the coldest time of MIS 2 and its extinction may be related to the cold climate. The number of Paleolithic sites rapidly increases from MIS 3 to MIS 2.

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 The chronological record of the woolly mammoths (Mammuthus primigenius) in Japan is reevaluated, on the basis of new and previously published and radiocarbon dates obtained from nine of the12 known specimens. The dates range from 45, 110 ± 480 to16, 320 ± 90 yr BP. However, the exact provenance of the youngest specimen, from Yubari, is unknown. Excluding this specimen, woolly mammoths appear to have been present in Japan from around 45 ka to 20 ka, although perhaps not continuously. Remains of Naumann’s elephant Palaeoloxodon naumanni, from Yubetsu eastern Hokkaido, gave a radiocarbone date of 30, 520 ± 220 yr BP. Since this species was adapted to temperate forests, and previous pollen analysis indicated there was a slight climate amelioration from about 34 ka to 26 ka (correlated with MIS 3), it is probable that P. naumanni temporarily displaced M. primigenius during this period in Hokkaido.
 The radiocarbon dates of the specimen from Cape Erimo (19, 580 ± 80 yr BP), the second Ogoshi specimen, and the first and second Yuni specimens (45, 110 ± 480 yr BP, 37, 410 ± 250 yr BP) settled the dispute of these horizons.

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 The internal texture of the recent and fossil proboscidean teeth was examined from the view point of the tooth development and evolution. Several species of the fossil Proboscidea from Japanese Islands, including genus Gomphotherium, Eostegodon, Stegodon, Palaeoloxodon and Mammuthus, and two living species, Asian and African elephants were observed by means of optical microscopy and scanning electron microscopy.
 In observation, it was focused on the distribution and arrangement of the Hunter-Schreger’s bands in enamel concerning multi-layered enamel and the shape and size of the enamel prisms in relation to the phylogeny and the formation of the molar structure.

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 After the introduction of biological techniques and methodology, paleontology revived as paleobiology, outgrowing the classical studies, which had hitherto been limited only to morphological description and classification. In Japan one outcome of the modernization in paleontology was the launch of the Fossil Club in 1959. Here were described the brief history on the foundation of the Fossil Club, the developments leading up to the Fossil Research Society of Japan, and then their contribution to paleobiology.

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 Reconstructing shark dentitions, using one or more sets of fossil teeth, has become a recent trend in shark paleontology. If a tooth set is defined as more than one tooth belonging to a single taxon, three major preservation types of tooth sets are recognized in the fossil record of sharks: isolated, associated, and semiassociated tooth sets. An isolated tooth set consists of isolated teeth and may represent more than one individual shark. An associated tooth set is a tooth set referable to one individual shark, and it can be either an articulated tooth set or disarticulated tooth set. A semiassociated tooth set consists of one or more disarticulated tooth sets and/or an isolated tooth set, and it includes two subtypes, feed-shed tooth set and coprolitic tooth set. A feed-shed tooth set consists of an assemblage of fallen teeth formed presumably during feeding, and a coprolitic tooth set represents teeth enclosed in a coprolitic matter. Complex taphonomic processes, including both before and after the recovery of teeth, may make an associated tooth set or semiassociated tooth set to become an isolated tooth set by means of disassociated teeth. For effective communication among shark paleontologists, it is important to accurately identify and record the preservation type of each tooth set used to reconstruct dentitions of fossil sharks.

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 The present study was designed to examine how the mineral elements of dentin change with the process of fossilization by using an energy dispersive X-ray fluorescence spectrometer (EDXRF). The EDXRF can analyze the chemical composition of hard tissue and identify the presence of crystal present. In the cementum-covered dentin of humans and whales, the Ca/P molar ratio was 1.83 and 1.82 (average), while the Ca/P molar ratio was as low as 1.55 (average) in that of Asian elephants. As these different species vary significantly in tooth size, tooth form, and tooth formation mechanism, it is suggested that these differences affect the chemical composition of dentin. In the fossil incisor of Gomphotherium sp. from a Miocene specimen recovered in Florida, the Ca/P molar ratio of dentin was high with an average of 2.02. This might have resulted from the reduction in atomic weight percentage of P, and suggests P may have flown out into the surrounding stratum during the process of fossilization. It is also presumed that vivianite was formed in the outer edge of the fossil. In the fossil specimens, the elements of Al, Si, Mn, and Fe were present in possible trace amounts. It is presumed that these elements entered into the dentin from the stratum. It is considered that some elements may enter during the apatite crystal formation. We conclude that the entering elements change with differences in the deposition environment or the fossilization process.

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