In the Japanese Islands, volcanic activities and geotectonic movements which have been very active since the later Tertiary, have exerted profound influences on the present landforms. Accordingly, stratigraphic and morphogenetic examinations of volcanic landforms and of geotectonic developments are extremely important. From this point of view, the writer investigated geomorphological developments of the eastern foot of the Zaô volcanoes and its environs. The Zao volcanic group is composed of four volcanoes: Aoso, Ryû-zan, South Zaô and North Zaô.
The results of this investigation are summarized as follows:
1) After deposition of the Numata Formation, Aoso volcano was being active throughout the first half of the Quaternary period when the initial form of this volcano was developed. It appears that the activity of the volcano started under a lacustrine environment. Therefore, most of the Aoso volcanic deposits show submerged facies.
2) When this volcano rose above the sea level, its activity stopped. A red weathered crust was created during the following warmer period over the initial surface of the volcano. Thereafter, the center of the volcanic activities moved toward the west of Aoso volcano, and South Zaô became active.
3) The activities of the Zaô volcanoes started again with South Zaô. Volcanic mudflows from South Zaô are three in number; namely, Karasawa, Kawarago, and Nanokahara. The Kawarago mudflow formed flowmounds and the Nanokahara mudflow formed a fan-like topography.
4) After the down-flow of the Nanokahara mudflow, the center of volcanic activities moved to North Zaô.
5) There are five topographic areas which are not of volcanic origin; namely, hill-lands, the Hara terraces, the Nagano terraces, the Nagafukuro terraces, and recent terraces, including fans and flood plains. The Nanokahara mudflow is related with the recent terraces.
6) In the Murata-Ôgawara area, terraces are not discernable, and this, as well as the hilly landforms, indicates the existence of geotectonic movements, the western part of this area shows an elevating tendency, whereas the eastern part has tended to subside. The boundary of these two movements closely coincides with the Komurasaki-Shiroishi geotectonic line.

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By statistical analyses of the geometry of drainage basins formed by fluvial processes, the author obtained some important knowledge related to the development of a drainage basin, and made clear the hypsometrical characteristics of the drainage basins of Japan.

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In general, the air temperature in an urban area is higher than in its suburbs. This fact has been confirmed by several investigations. Today, many studies are conducted to solve the reasons why an urban area is warmer than its surroundings. As a step to clarify this problem, it is necessary to study the relationships between the distribution of air temperature and several conditions, for example, weather, condition of the earth surface, the urban structure, and so on. Among these conditions, the wind seems to vary the distribution patterns of air temperature in an urban area. The author describes the relationships between the distribution of temperature and the wind (especially the horizontal air flow) in this paper as quantitatively as possible. Data used for this analysis are from climatic observations in Kumagaya City, situated in the Kanto plain. The observations were repeated from September, 1956 to March, 1957, by the Research Croup for City Climate in Japan. Air temperature was observed by the thermistor electric thermometer which was installed on the front bumper of a car. Observation points were distributed on two lines (Fig. 1) One is Nakasendô (Highway No. 17) running through thee urban area longitudinally (from ESE to WNW), and the other is a road crossing Nakasendo (from NNE to SSW). Thus 36 sections of temperature distribution were obtained in Kumagaya City for each distribution (Figs. 2 and 3). Some similarities of pattern are shown between these sections. The author devided these sections into several groups based on the similarities of section patterns. This grouping was made by using “correlation by rank method” in order to obtain more objective results. Thus 21 sections among the 36 were grouped into 4 groups for longitudinal sections of temperature distribution, and 25 sections among the 36 were grouped into 5 groups for cross sections. The patterns of these groups have different features, for example, the points of highest or lowest temperature differ. These differences in the patterns of distribution seem to occur partly with different wind conditions. So the author collected data for the average wind speed and the prevailed wind direction for each observation. From these data, the ESE-WNW and NNE-SSW components (V_ESE and V_NNE) of the wind were calculated respectively and averaged for each group (V_ESE and V_NNE). Next, he tested the significance of the difference of V_ESE for each group by “the variance analysis method” As a result, it was clarified that the differences of mean values of V_ESE for each group (V_ESE) were significant at the 1% level. The same result was obtained for the V_NNE.
Considering the facts above mentioned, maps of temperature distribution in several wind conditions were drawn. (Fig. 4.). Marked differences in the distribution pattern according to wind conditions are also recognized. From these studies, the following facts may be pointed out:
(1) The distribution patterns of air temperature in an urban area are affected by advection.
(2) To some extent, the actual states of temperature distribution in an urban area are made clear by the longitudinal and cross sectional observation methods.

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In this study the size, roundness, and flatness of beach pebbles on the beaches of Ukishima, Miho, Kôchi, and Kumanoura on the Pacific coast of Japan are examined. These coasts afford ideal opportunities for a study on the processes of transportation and deposition of beach sediments, and, except for the case of Kumanoura, large-scale charts and various other useful data such as of wave period, wave height, and wind velocity, all of which may contribute to the solution of these problems concerning beach pebbles, are to be found easily.
Conclusions drawn from this study are as follows:
(1) The grain sizes of beach sediments are similar to those of stream sediments which are supplied to beaches. Ratio of gravels in beach sediments has a relation neither to that in the stream sediments, nor to the intensity of wave action, but is related to both beach slope and offshore bars.
(2) As seen in Figs. 2, 6, and 10, several zones of grain size are distributed on a beach where the grain size of beach sediments gradually decreases from upper (inland) to lower part (seaside). Between the zone of sediment and the zone of swash exists a close correlation. Generally, these zones show a complicated feature on the foreshore and the lower backshore, but a simple feature on the upper backshore. This fact can quite simply be explained in terms of the number of waves reaching the shoreline.
(3) Distance of transportation of the same grain size along the shore on each beach is mutually alike. It seems that the properties of wave resemble each other. From this phenomenon it may be possible to say that the gravels with a diameter of 256mm or less are transported to a distance on the Pacific coast of Japan. In general, the pebble size varies in accordance with the difference of pebble quantity, topography, and beach slope.
(4) Even such hard rocks as chert become considerably rounded by abrasion. Change of roundness from the river mouth to a further point on the beach is not abrupt but rather gradual. If the sediments move on the bedrock or are deposited at the same place for a long time, roundness of pebbles increases rapidly.
(5) A proportional relationship between roundness and flatness also exists, i. e., the rounder the pebble becomes, the flatter it is. But in case of smaller grain sizes, the relationship is obscure. It is because that abrasion process is different between larger pebbles and smaller ones or granules. It is probably ascribed to the fact that the larger ones move only occasionally, so that their exposed surfaces are worn off by the wash of finer materials, but finer pebbles and granules are worn off quite uniformly by rolling, resulting in a spherical shape.
(6) A study of 32-16 mm graywacke pebbles shows that, if the average roundness is more than 0.60 and the average flatness is more than 0.40, these pebbles can be considered as beach pebbles.

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