The Tsugawa and Mikawa Sedimentary Basins, situated in the southern part of the Inner Zone of Northeast Japan, are composed mainly of Early to Middle Miocene "Green tuff" formations. The Miocene Series distributed in the western part of both basins are divided into the Kanose, Tsugawa, Tenman and Tokonami Formations in ascending order. The Kanose Formation is subdivided into two members; the lower Akaiwa Member (0-100 m thick) consisting of conglomerate and sandstone, and the upper Minowasan Member (20-130 m thick) being composed of silisic volcaniclastic rocks. This Formation unconformably overlies the basement of Mesozoic sedimentary rocks. The Tsugawa Formation overlies the Kanose Formation with partial unconformity, and is subdivided into two members; the lower Yagiyama Member (60-700 m thick) being composed of arkosic sandstone, conglomerate and mudstone, and the upper Fukutori Member (100-400 m thick) consisting of silicic volcaniclastic rocks and lava flows. Both members increase in thickness to the south. The Tenman Formation conformably overlies the Tsugawa Formation, and is subdivided into three members; the lower Shinazawagawa Member (0-300 m thick) consisting of sandy mudstone, the middle Hanatate Member (50-300 m thick) being composed of silicic volcaniclastic rocks, and the upper Nomura Member (100-400 m thick) being of mudstone with some basaltic volcaniclastic rocks. The Tokonami Formation (140-200 m thick) consists of mudstone and sandstone, and unconformably overlies the Tenman Formation. The rhyolitic dykes are scattered in the most area, but the distribution of basaltic intrusive rocks are limited to the northern area. In the central to southern parts of the Tsugawa Basin, the N-S trending asymmetric Kumowada Syncline with steep western flank is conspicuous. In contrast with this, the strata dip gently to the west, in the northern Mikawa Basin. On the whole in the study area, N-S, NW-SE and NE-SW trending faults and dykes are dominated. Summarizing the geologic development of this area, differential depression took place during the deposition of the lower member of the Kanose Formation, after then, during the deposition of the upper member, gentle uniform subsidence occurred, and a considerable part of the area was submerged beneath the sea. The southeastern part of the area, where the Kanose Formation is not distributed, uplifted during the deposition of the formation. At the end of this stage, ash flow erupted from this uplifted area, followed by the depression of the Tsugawa Basin.

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The Pliocene Yadagawa Formation in the Naruko Hill, east of Nagoya, is composed of fluviatile-lacustrine loose sediments. It is lithologically divided into three members, namely, the Nisshin, Takahari and Idaka Members in asending order. The total thickness attains to 110 m. The Nisshin Member, more than 10 m in thickness, are composed of alternation of sand and mud beds. The Takahari Member, 50 m in thickness, is composed of alternation of gravel, sand, silt, and clay beds. The Idaka Member, more than 50 m in thickness, is characterized by gravelly beds with intercalation of sand, silt and clay beds. The Yadagawa Formation shows a homoclinal structure with N-S strike and gentle dip to the west. Five volcanic ash layers are intercalated in the Yadagawa Formation. They are named the Togo, Nagakute, Kumanomae, Takinomizu I, Takinomizu II volcanic ash layers in ascending order. On the basis of the tephrostratigraphy, the Yadagawa Formation in the Naruko Hill is correlated to the middle and upper parts of the Yadagawa Formation in the Owari Hills. The following plant fossils occur in the lower part of the Idaka Member: Fagus palaeocrenata Okutsu, Quercus serrata -Thunb,, Quercus variabilis Blume, Styrax rugosa Miki, etc.

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Many rootless fumaroles are found in the upper unwelded part of the Noboribetsu Pumice Flow Deposit-I (dacitic in composition; about 40,000 years old), which is distributed around the Kuttara Caldera, southwest Hokkaido. Alteration due to the fuma-rolic action extends into the Noboribetsu Base Surge Deposit overlying the Pomice Flow Deposit-I. The number and size of the rootless fumarole are larger, and also the degree of alteration is stronger in Kaminoboribetsu, about 4 km west of the Caldera, whereas the size of the rootless crater pits tend to increase in Satsunai, about 6 km southwest of the Caldera. The alteration part is usually reddish but white or dark reddish brown to almost black in strongly altered part. The characteristic alteration minerals determined by X-ray diffraction are: (1) kaolinite from the Noboribetsu Base Surge Deposit, (2) montmorillonite from the white part of the Noboribetsu Pumice Flow Deposit-I, and (3) hematite, natroalunite, and 10 A halloysite from the various parts of both the Base Surge Deposit and the Pumice Flow Deposit-I. The dark reddish brown color resulted from hematite.

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Thick Neogene to Quaternary deposits, the Tokachi Group, are distributed extensively in the Tokachi Plain, eastern Hokkaido. The lower part of this Group, the Honbetsu, Ashoro and Ikeda Formations were investigated with pollen analysis. Two pollen zones, Picea-Tsuga-Alnus Zone and Fagus-Alnus Zone were discriminated, and each zone was subdivided into Subzones I〜III in ascending order. 1. Picea-Tsuga-Alnus Zone (Latest Miocene〜Early Piocene) is generally characterized by high frequencies of fossil pollen Picea, Tsuga, Alnus and Juglans originated from temperate〜cool temperate slope forest. In Subzone II, pollen frequencies of broad leaf trees such as Ulmus〜Zelkova, Quercus, Tilia and Carpinus are reratively higher than those of Subzones I and III. 2. Subzone I in Fagus-Alnus Zone (Early Pliocene) is characterized by high frequencies of fossil pollen Fagus, Alnus, Tsuga and Picea originated from temperate〜cool temperate forest. It was a transitional stage from Picea-Tsuga-Alnus Zone to Subzone II in Fagus-Alnus Zone which is dominated with Fagus and Alnus. Climatic condition of Subzoue II is represented warmer and moister than that of Subzone I. However, the pollen assemblage obtained from Subzone III (Late Pliocene) suggests that it deteriorated to cool climatic condition. The characteristic of Fagus-Alnus Zone is correlated with that of Pliocene Hukagawa Group which are distributed in the Takikawa and Hukagawa district, Hokkaido.

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Five specimens consisted of three genera and five species of chondrichthyes from the Middle Permian Akasaka Limestone in Kinshozan, Akasaka-cho, Ohgaki City, Gifu Prefecture, Central Japan are described. The fossil horizon is the uppermost part of the lower division (zone of Parafusulina). The chondrichthyan fossils were found in the pale orange and dark grey part of the grey-white massive limestone, and cotaining fossils such as Parafusurina japonica (Gumbel), Yatsengia ibukiensis Minato, Coelogasteroceras giganteum Nakazawa, ? Agathiceras sp. and crinoids. They are two teeth of cladodont sharks, Symmorium sp. and ? Symmorium sp., two dermal teeth of petrodi, Petrodus sp. and ? Petrodus sp., and one tooth plate of cochliodonts, Chochliodontidae gen. et sp. indet. Symmorium sp. is represented by a well preserved large cladodont type tooth. There are five cusps: a large central main cusp, mesial and distal side cusps and two small accesory cusps which are situated between main and side cusps. The main cusp is slightly inclined distally. There are many fine striae on the surface of the crown. The root of the tooth is composed of osseous tissues. ? Symmorium sp. is represented by a very small cladodont type tooth. The root and the mesial side cusp are not preserved. The cusps are straighter than the cusps of Symmorium sp. There are many fine striae on the surface of the crown. Petrodus sp. is a very large dermal tooth which is almost completely preserved. It is conical in shape. There are about thirteen radiating plicae and several circular growth lines on the surface of the crown. ? Petrodus sp. is one side of longitudinal section of the dermal tooth. It consists of two layers. The outer layer is thick and composed of white enameloid-like hard tissue which has many tubular structures. The inner layer is composed of black dense materials The tooth plate of cochliodonts, Chochliodontidae gen. et sp. indet., is observed from both sides in labio-lingual section. It is a large, curved, orally convex plate. There are five ridges on the occulusal surface of the tooth plate. The lingual ridge is largest and the other ridges become low and small towards labial side. It consists of three layers. The surface layer is thick and composed blue-grey enameloid-like hard tissue. The middle layer is composed of thin black substance. The basal layer is composed of dark grey hard tissue which is pale in some parts. This paper is the first report of cladodont type tooth of elasmobranchs, dermal tooth of petrodi and tooth plate of cochliodonts from the Japanese Permian. It can be expected that many kinds of fossil fishes will be found from the Paleozoic of Japan, in future.

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