Extant frilled shark, Chlamydoselachus anguineus, is the most primitive shark in living elasmobranchs based on their anatomical characteristics. Based on the former data, the oldest record of chlamydoselachidae was Chlamydoselachus thomsoni reported from the Campanian (Late Cretaceous) of James Ross Island, Antarctica. In this paper, six species of twelve specimens of Chlamydoselachus from Japan, that is, five species of ten specimens from the Turonian to Maastrichtian, Upper Cretaceous formations and one species of two specimens from the Miocene, Tertiary formations are described and phylogenetic relationships and paleoenvironmental changes of chlamydoselachians are considered.

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The authors found ground water origin manganese nodules which were been in the Oppu Mine in Aomori Prefecture, Japan. The manganese nodules have formed in less than 15 years. The manganese nodules sized between granule and pebble occurred with manganese crust in the well-developed seem microbe of mat materials. Microbe material are present in cores and surface of some manganese nodules. All of the manganese nodules were spherical and having layered structure which were classified into s-m[SDP]s or s-m[SDP]s+r types according to deep-sea manganese nodules form (Meylan 1974). The manganese nodules are existent with microbe materials suggesting the genetic relation to the microbe materials.

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Field and laboratory studies were conducted to investigate the successive changes in the chemical and physical characteristics of rainwater through stemflow as well as soil in three different forest ecosystems. That is, Sugi (Cryptomeria japonica), Konara (Quercus serrata), and Mousoutiku (Phyllostachys heterocycla) forests which are located in the Kakuma campus of Kanazawa University, Ishikawa Prefecture, Japan. Rainwater outside those forests was also sampled as control precipitation. For field investigation, the rainwater samples as throughfall and stemflow were collected from February 25 to March 18, 2004. For laboratory investigation, the batch leaching experiment using control rainwater was performed over a period of one week, and the continuous filtration experiment using downflow soil bed system with the stemflow of those trees was undertaken as well. XRD analyses of bulk soil and < 2 μ m fraction of soil samples collected from those forests showed similar mineral compositions composed of quartz, feldspars, cristobalite, gibbsite, chlorite, vermiculite, and kaolin minerals. The leaching experimental data showed similar mineral decreases in the rainwater pH of Sugi forest (pH〜4), while little change in the rainwater pH of Konara forest was observed. Conversely, the rainwater pH of Mousoutiku forest tended to increase. These pH changes may be the result of dissolution of K and Ca contained in the bark of those trees in agreement with the experimental data of chemical composition of rainwater analyzed by ED-XRF. Scanning electron microscopic observations of tree bark showed that the surfaces of bark after leaching became smoother than those before leaching, and their EDX spectra showed that there were decreases in the K and Ca contents after leaching. The continuous filtration experiment demonstrated that there were significant changes in the pH, EC, and Eh of the effluent rainwater after filtering through a soil filter bed with several kinds of minerals, indicating that minerals serve as a natural buffer. These results indicate that the type of plants and mineralogical composition of soils in forest ecosystems have effects on the successive changes in the chemical and physical characteristics of rainwater.

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Pliocene "Sasamoriyama andesite" is distributed in the southwestern margin of the Fukushima City, consisting of the volcanic front of northeastern Honshu arc at that period. We have obtained nine K-Ar ages from the "Sasamoriyama andesite". Three samples located in the southeastern part of the distributed area are about 3.7 Ma and 3.0 Ma in K-Ar ages. The other six samples situated in the northwestern part are all younger, having K-Ar ages between 2.4 and 2.0 Ma. Consequently, Pliocene volcanic activity had been started in southeastern part at 3.7 Ma. And after that, volcanic activity of 2.4 to 2.0 Ma moved northwestern direction to the back-arc side. The older volcanic rocks mainly consist of pyroxene andesite lavas containing large anorthite phenocrysts, whereas the younger volcanic rocks consist of pyroxene andesite without anorthite phenocrysts. Both of them are classified into medium-K, low-alkali suites. However, the older rocks contain both of tholeiite and calk-alkali rocks, while the younger rocks contain only calk-alkali rocks.

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Two Early Carboniferous (late Visean to Serpukhovian) brachiopod species, Echinoconchella sp. and Gigantoproductus sp., are described from limestone floats at Tsuchikurazawa, a tributary of Kotakigawa in the Omi area, central Japan. The occurrence of these brachiopods suggests that the limestones of Tsuchikurazawa, derived from limestone blocks of the Middle to Upper Permian Kotaki Complex, were probably originated from the lowest part of the Ichinotani Formation (upper Visean to Serpukhovian) of the Fukuji area, Hida Gaien Belt or its equivalents. This indicates that the Akiyoshi Terrane including the Kotaki Complex was accreted at the front of the Hida Gaien-South Kitakami-Kurosegawa continental shelf, developed on the eastern margin of North China (Sino-Korea) in the Middle to Late Permian time.

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