The investigation of the landslips in Volcano. Akagi was made by the writer from spring to summer in 1952, and it covered an area of 558km² in which landslips of 1126 in number were actually observed. The results may be summarised as follows: -
_??_1_??_ The landslips in Mt. Akagi are found to be more abundant (a) in the area where the initial surface of the volcano is youthfully or submature-ly dissected, (b) on the slope occupying the upper half of the valley wall and (c) in the valley section above knick points. _??_2_??_ The shape of the slipped surface differs according to the character of the rocks, though the shield-shaped ones prevail on the whole. _??_3 _??_ The scale of landslips is generally smaller in palaeozoic rock regions, but is not found to have any-thing to do with the general inclination of the slipped surface. _??_4_??_ The direction of slipping is in most cases at right angle to the trend of the river. _??_5_??_ In the above investigation, erosion has been found to have gone, farthest in stage in the southern area of the mountain, less in the western, and least in the northern. It may be related to the speed of erosion.

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There are two groups of wave-cut benchs, beveling the Tertiary sedimen-tary rocks, along the coast of Aburatsubo Bay, Zyogashima Island and cape Kengasaki in the southern part of the Miura Peninsula. The higher, eleva-ted benches which were uplifted at the time of the Great Kanto Earthqua-ke in 1923 largely develop at the tip of the capes where the wave action is most vigorous. The lower benches lie below the high tide level and pre-vail along the coast of the calm inlets (Fig. 1). The surface of the elevated benches of which features are controled by the geologic structure and the hardness of rocks slightly incline landward, while the, lower benche have a smooth surface with a gentle seaward inclination and no relation to the rock formation (Fig. 2). Moreover the higher and the lower benches differ in many respects. Accordingly the auther has concluded that the elevated benches have characters of the storm bench, and the lower benches are almost similar to what was called the “Old Hat type bench” by Bartrum (1926).

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