Hitherto, various reports on the stratigraphy, geomorphology and mineralogy of the Kanto volcanic ash have been published, however, any geochemical study of it has never been known. So the writer has performed the study on this line, in order to get some new criteria from view for the determination of its geological horizon and their origin, and for the clearance of mechanics of their effusions. Selecting the ferromagnetic minerals, as an index mineral of the former facts, he studied the general characters of chief pumice layers embeded in the Kanto volcanic ashes in whole Kanto district. Most of ferromagnetic minerals included in the pumice layers, are titanomagnetite belonging to FeOFe2O3-TiO2 system with spinel structure and posses the chemical composition which deviates considerably from TiFe2O4-Fe3O4 join towards TiFeO3Fe2O3 join side. And it is common that a few ferromagneilmenite coexist in titanomagnetite as lamellae. He found that the chemical composition of titanomagnetite belonging to the same geological horizon are varied due to their grain size, and he considered the course of it. In one pumice layer, TiO2 content decrease gradually from the bottom to the top of it. And especially in a pumice layer covering wide area, the former change of TiO2 content repeat twice or three times. Most of pumice layer belonging to the same geological horizon, though the covering area of them is varied, have the same chemical composition of ferromagnetic minerals. There fore their chemical composition are able to use as a criteria for the determination of their geological horizon. But their chemical composition are often allied in spite of the difference of their geological horizon, so it is difficult to decide at once their horizon and origin from the chemical composition of them. From the view point of the mechanics of effusion of voluminous pumice fall, however it is interesting fact that they have allied chemical composition in spite of their variance of their geological horizon.

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The core samples, obtained atSeijo-machi, Setagaya-ku, Tokyo, were examined pollen-analytically. The silt layer which contains these samples situates in the depth from 14.0 m to 23.3 m. This silt layer is stratigraphically correlated to the upper part of the Tokyo formation and which is corresponded to the middle mud-layer of the Shimosueyoshi formation. The results of the pollen analysis are following, 1) Lower part; (depth : 22.0-22.3 m) The genera indicating relatively cool climate are generally appeared. 2) Middle part; (depth : 16.0-21.3 m) Alnus and Ulmus or Zelkova are predominant. In this part, the remarkable changes of the predominant genera are not shown. 3) Upper part; (depth : 14.0-15.3 m) Tsuga and Cryptomeria are predominantly recognized. According to these results, the climatic conditions of the upper Tokyo formation are considered as follows: 1) In the uppermost part and in the lowermost part, there are relative cool periods. 2) The palaeo-climate appeared in the upper Tokyo formation is similar to or slightly. cooler than the present time.

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In Kinki District, Southwest Japan, the Plio-Pleistocene series are widely distributed, namely, the Osaka group and its correlatives. The Osaka group is divided stratigraphically into three parts, the lowermost, the lower and upper parts, and of them the upper part is considered to be the deposits of the age of the First Interglacial and the 2nd Glaciation (Mindel). In this paper, the writer described the pollen fossils of a boring core which was obtained from Sakai harbour. The materials treated ranged stratigraphically from Ma 2 marine clay bed to Ma10 marine clay bed. Further, he discussed the changes of flora, paleoclimate and paleoecology of the time of the deposition of the Upper Osaka group, and pointed out the fundamental problems concerned with the interpretation of pollen diagrams. 1) The pollen zones of the Upper Osaka group were divided into the Fagus and Pinanceae Zones in ascending order, and each zone was subdivided into subzones as shown in Fig. 4. 2) The warm and humid climate beginning with Ma 3 marine clay bed was followed by the warmer and more humid climate of Ma 6 marine clay bed. After that, the deterioration of climate took place (also shown in Fig. 4). The ecological characters of the forest flora changed evolutionally in the process of climatic oscillations, and the forest zones were differentiated more clearly by repeated arrivals of the glacial stages. 3) Vegetations of the non-marine phases were reconstructed by interpreting the pollen diagram, and it was pointed out that the influence of differential floatation and deposition of pollen has to be considered in making comparative study of the pollen-analyses of sandy and clayey sediments. 4) The stratigraphical horizon and process of disappearance of Liquidambar were discussed palynologically.

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The purpose of this report is to study the relationship between soil temperature and geographical location (altitude andlatitude). The air temperature is expressed as the function of latitude φ and altitude H, and the experimental equation is expressed as follows; spring θa=43.5-1.07φ-0.0056H* summer θa=36.7-0.52φ-0.0050H* fall θa=43.4-0.93φ-0.0050H* winter θa=44.2-1.33φ-0.0060H* annual mean θa=40.7-0.93φ-0.0052H* H*=H-1,000 These eqations indicate average air temperatures of three months in each season. The following are the experimental equations to get the variation of the air temperature (Δθ) in each season. spring Δθ=0.32φ-0.6 summer Δθ=0.28φ-5.3 fall Δθ=0.30φ+0.8 winter Δθ=-0.07φ+5.3 The average lapse-rate of air temperature in mountainous region are 0.59℃/100m in spring, 0.56℃/100m in summer, 0.58℃/100m in fall, 0.72℃/100m in winter and 0.61℃/100m in annual mean. The lapse-rate of air temperature is greatly influenced by the arid Sibelia air-mass in winter and by the humid Ogasawara air-mass in summer

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