In his previous papers, the writer has shown a peculiar contrast of the geoglogic structures of the lower Pliocene strata inn the Fossa Magna and in the outer zone of southwest Japan. And' he has concluded that. the structural lines of the.. lower Pliocene deposits do not conform with the general trend lines of the Honsyu arc or with the main structural lines of the outer zone of southwest Japan, but with the trend of the contour lines of the summit level in the outer zone of southwest Japan, and that the attitude of the lower Pliocene strata wasere made by the Pliocene crustal movements. From the above conclusions, . he has called in question that the crust deformation of the similar tendency as in the Pliocene crustal movements may have been continued during the later geologic period. In this paper he takes note of attitude of the. lower Pleistocene deposits and the inclinations of 4 coastal terraces arranged in step. on the southeastern coast of Kyûsyû. And he points out that the dips of strata and the inclinations of the terraces are the older, the steeper they incline towards E. or EES., and the crustal movements of the similar tendency have been continued or repeated in these districts since the early Pliocene age. And he inclines to conclude that the recent structural features of the lower Pliocene deposits in the outer zone of southwest Japan may represent the total result of the crust deformations accumulated slowly since the early Pliocene age.

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The distribution map of forms of settlement, Fig. 1, shows that there are four kinds of region on this fan. Namely the region of aggregate settlement, mixed settlement, dispersed settlement, and isolated homestead. In this report the auther tried to explain principally the natural environment of these four regions.
(1) In the region of aggregate settlement, central towns along high ways, fishingvillages along coast line, villages along foot of mountains and groups of houses which gather at fit places to avoid wet rice fields, exist.
(2) The regions of mixed settlement where groups of houses and dispersed houses are mixed extend at the bordering part of the fan and at natural levees of the flood plain of the Ogawa Rver. The Ogawa is smaller than the Kurobe and makes a compound fan with the Kurobe at the north-east part of the fan.
(3) The regions of dispersed settlement where the number of isolated homesteads equals to the number of homesteads in groups consisted of two or three homesteads, extend principally on the middle and vertex part of the fan under the terraces and small part on the terrace. These regions and next regions of isolated homesteads exist side by side in radial directions from vertex of the fan, but the former regions may coincide with somwhat higher zones.
(4) Regions of isolated homesteads extend on somewhat lower zones on the middle and vertex part of the fan and on the terrace. These somewhat lower zones are thought to be used to suffur from flood and accordingly perhaps may be newly-opened region. On the terrace there is no river to irrigate here sufficiently, so this terrace perhaps may be region where man could not get irrigation water until works of three irrigation canals of large scale are constructed.

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1. It is a remarkable fact that so-called landslides give very often awful damages to people, cattle, houses and others,
2. When a lands'ide takes place, the spot may in general be hollowed like an imperfect basin, and surrounding its upside there develops a new steep slope, from which ground water is apt to ooze out.
3. The basin thus formed is suitable for culture and habitation as we see in fig. 1 and fig. 3.
4. There is a tendency, in the area where landslides had formerly occured, to repeat the accident at the same spot or the adjacent area. If the region is habitated, the damage may be greater.
5. I intend, moreover, to, sketch (1) some topographic characteristics of landslide, (2) hills formed by mudavalanches, and (3) landslides caused dy heavy rains.

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