Marine terrace of about 50 m. (or 70 to 20 m. in precise) above sea level is recognized entirely around Japanese Islands. This terrace is named "Shimosueyoshi Terrace" in Japan. The terraces of such height are known all over the world. They are regarded as the traces of ancient sea level in non-glacial age of late Pleistocene.

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Main coastal terraces in Japan are aluvial-plane (0-10 m), Shimosueyoshi-plane (30-40 m) and Tamaplane (70-100 m) in ascending order. These three topographic planes have been formed by three transgressions during Quarternary period. The mode of occurrence of these planes, the older one shows higher altitude and inclination, which is resulted by Quarternary tectonism.

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The Shimosueyoshi, the Tokyo and the Narita formations were deposited at the time of the most extensive marine transgression; namely, the Shimosueyoshi Transgression. The correlation of this stage with the European standard succession is now being discussed in Japan, but it is usually accepted as the Last Interglacial. The previous concept of the Paleo-Tokyo Bay is here emended on. the basis of newly賓btained evidences concerning the paleogeomorphology as shown by the contour map of the basal boundaries of these formations, the stratigraphica relations with the underlying rocks, lithofacies changes and molluscan fossils. The inferred paleogeographical change of the Kwanto Plain is illustrated.

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On the purpose of the explication of the relation between the crystallization advance of the volcanic ash and the geological time or the condition of sedimentation, the writers have studied the clay minerals in the Kanto loam formation by means of X-ray, differential thermal analysis and the electron microscopic observation. This research carried the following conspicuous results on the properties and occurrence of clay minerals in the Kano loam formation. (1) The principal clay minerals are allophane and hydrated halloysite, and the general mineralogical features are recognized. (a) The Tachikawa loam formation corresponding to the uppermost part of the Kanto loam formation is largely composed of allophane. (b) The Musashino loam formation covered with the Tachikawa loam formation is mainly composed of hydrated halloysite associated with a small amount of allophane. (c) The Shimosueyoshi and the Tama loam formations correlated to the lower part consist of hydrated halloysite in the aeolian deposits and in the marine deposits the random mixed layer mineral of halloysite and hydrated halloysite. It is stated that the clay mineralogical variation from allophane to hydrated halloysite is intimately related to the geological time of sedimentation of the Kanto loam formation. (2) The writer researched extensively the volcanic ash in the Kanto district on the view of clay mineralogy. In the northern part of the Kanto district the upper loam and Al members correlated to the Tachikawa loam formation are composed of allophane. The middle loam and A2 members correspond to the Musashino loam formation and their clay mineralogical features are similar to that in the Musashino loam formation. The lower loam, and A_3 and A_4 members are correlated to the Shimosueyoshi and the Tama loam formations on the clay mineralogical features as well as the stratigraphical evidences. (3) The random mixed layer mineral of halloysite and hydrated halloysite in the Shimosueyoshi loam and A_3 members is largely included in the specimen from the marine sediment. Furthermore the mode of distribution of this mineral is related to the Shimosueyoshi transgression. The specimens obtained from the central part of the Paleo-Tokyo Bay in the Shimosueyoshi transgression period are mainly composed of the random mixed layer mineral and specimens in the vicinity of the margin of the Paleo-Tokyo Bay consist of the mixture with hrdrated halloysite and above mixed layer mineral. By these reasons the writers are revealed the possibility of application of the clay mineralogical features to the stratigraphy and paleogeography.

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The latest studies of the Quaternary stratigraphy in Japan have advanced intensively. Based upon them and referring the palaeoclimatological evidences, the author proposed the revision of the Quaternary chronology in Japan from the view points of the mammalian faunal succession in this paper. The Early Pleistocene (Villafranchian s. 1.) fauna in Japan is the Parastegodon faunas including the Akashi-, the Umegase faunas, and is characterized by Parastegodon akashiensis, P. aurorae, Parelephas proximus, Metaplatyceros sequuoiae, Elaphurus davidianus, Cervus kazusensis etc.. Formerly, they were considered as immigrant of the Malayan elements, but now, the author treated them as the endemic fauna of the "Tertiary" type. Those had disappeared in parallel with the extinction of the Metasequoia flora before Gunz glacial age. Taking the place of that fauna, Stegodon-Palaeoloxodon fauna which was the immigrant of the Chinese Stegodon-Ailuropoda fauna (s. 1.) (Sino-Malayan type) appeared in the early Middle Pleistocene. They are Stegodon orientalis, Palaeolxodon namadicus naumanii, Dicrorhinus shindoi (D. mercki type), Cervus praenipponicus, Giraffa, Buffelus, Sus, Ursus, Macace etc. This fauna includes the Sanuki-, Nan jo-, Kusae-, Saginota-, Matsugae-, Lower Kuzuu faunas. In consequence of the subsidence around the Japanese islands at the time of late Mindelparoxysmal crustal deformation, the land connections to the Asiatic continent are supposed to have been lost. Then, the Stegodon-Palaeoloxodon fauna might been isolated and their descendants were continued till the Warm glacial age comes. Thereafter, the late Middle Pleistocene mammalian faunas were very poor and were represented merely by Palaeoloxodon namadicus naumanii and "Parelephas trogontherii". The Riss/Warm transgression, so-called Shimosueyoshi transgression, were recorded in the marine sediments of various localities in Japan. From those sediments, Palaeoloxodon namadicus naumanii and its specialized varieties had been reported abundantly. It is possible to say that the formation of the Tsugaru strait between the Honshu islands and the Hokkaido island were perfomed at this time. Nowadays populations of the mammalian fauna in Japan (the Honshu islands) are composed chiefly by the Manchurian elements (elements of the northern temperate zone and the frigid zone). The first appearence of those elements were found in the Upper Kuzuu fauna. That fauna was considered to be nearly equal with the Sjara-Osso-Gol fauna of the Northern China. In Japan, the stratigraphical horizon of this fauna is the last part of the Late Pleistocene, probably Warm I. Then, the immigration of the Manchurian elements would be possible in consequence of the land bridge formation at the time of the Warm sea level lowering. The Bison-Equus (E. hemionus) fauna, eg. the Hanaizumi-, the Tsukinoki fauna of North Japan, and the Mammonteus primigenius fauna of the Hokkaido are considered to be also Wurm time (Warm II). Perhaps, the Late Palaeolithic man might also be introduced into the Japanese islands in the same time and along the same courses as above. Palaeoloxodon namadicus naumanii and its allies were discovered with them.

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下末吉階とその相当層の堆積物の花粉分析の結果によると,(1)下末吉階の気候は現在とほぼ同じ位の気候であった.(2)北陸地方の下末吉階の地層の発達している平床台地,および江沼台地では,平床期海進の初頭には現在よりもやや冷涼であったが,海進中期には現在とほぼ同じ位の気候になった.

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The stratigraphical distribution of the flora which has occurred from the Pleistocene and late Pliocene series is as shown in Table 1. At the Wurm glacial age, the vegetation in the northeastern Honshu may have been represented by the subalpine coniferous forest intermingled with the broad leaf trees, such as Fagus crenata, Quercus crispula and Tilia japonica. At the Riss-Wurm interglacial age, the vegetation in the northeastern Honshu may have been represented by the broad-leafed forest growing in the low mountains and hills intermingled with the species, such as Fagus crenata and Picea Glehni. The several species such as Picea Glehni, P. jezoensis, Abies sachalinensis, Pinus koraiensis, Manyanthes trifoliata and Phellodendron amurensis show an interesting distribution severally in the Eastern Asia. The writer described the stratigraphical distribution of the above mentioned species in Honshu and considered their migration.

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1. Three morphogenetic regions basing upon the modes of water in nature-the geomorphic agent, are explained. 2. Vertical distributions of climatic and vegetational zones upon high mountains in Central Japan are discussed. The present snowline over the Japan Alps is considered to stand at the level of about 4,000 m in altitude. 3. During the Wurmian glacial, the snow line may have depressed by about 1,300-1,500 m and the forest limit line also by about 1,000-1,500 m. 4. The structure soil limit line is nearly the same as the present forest limit line and also as the Wurmian level of the snow line. 5. Owing to intensive crustal movements that might have hitherto taken places in Japan, it is rather hard to detect if there was a time of periglacial accumulation.

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