Recently, rhythmic land forms such as shoreline waves, rhythmic system of arcuate bars, and the meandering of the longshore current along beaches have been pointed out by means of accurate hydrographic survey and aerial photographic interpretation. On the other hand, rhythmic patterns on the sea bottom such as sand waves are found in the areas with strong current and sandy bottom.
The author recognized some resemblances in the configurations, composing materials and their movements between the shoreline undulations and sand waves. On the offshore bottom with the more depth, the water and the sand particles are able to move vertically to the sea bottom. While, on the nearshore bottom with little depth, the water and the sand particles are able to move horizontally to the shoreline. Both the shoreline undulations and submarine sand waves are facing the cape like cusp or crest perpendicular to the direction of the nearshore and offshore currents. Accordingly, the relations between movements of water and sand particles and these rhythmic topographies are very close to each other.
From these reasons the author assumed that there is a similar mechanism on the origin of the both rhythmic topographies.
He, then, presented hypothesis that the shoreline undulation and submarine sand wave were formed by the water circulations or vortices resulted from the meandering of currents caused by the occasional disturbance of currents.

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This article is made with purpose to distinguish the limits of Keihin Industrial Area in Pan-Kanto Industries. Keihin Industrial Area can produce a third of all industrial additional value in Japan. The industries, in local industrial area in Kanto Area, consist of (1) the industrial group of nonferrous metals, wooden furnishings, milling, starch, marine processed foodstuffs, cement, earthenware and imitation stone in ceramic-quarrying industry, (2) the group which comes from fiber industry, (3) the group which springs up in the central cities of the districts and (4) the assemblage industry which adopts knock-down systems.
The assemblage industry is the main feature in Keihin Industrial Area. The area, however, is extremely limited and distinguished from North-Kanto Area of which industries have their origin in the fiber industry, when regarding the districts, where the ratio of assemblage industry accounts for a third of whole additional value produced in 1960, as Keihin Industrial Area. After minute investigation, we find that there exists former cotton culture area lying between North Kanto Industrial Area based on the silk industries and Keihin Industrial Area. While the cotton culture area disappeared in the stage of farmers' manual labor, the production system in the silk industrial area organized with the wholesalers at the center was smoothly changed into the modern industries. That is considered the cause of gapping between Keihin and North Kanto Industrial Areas.
According to the above mentioned, we can say that the existence of preceding industry and investment is necessary for the formation of modern industrial area, and we consider, without either of the two, collective modern industrial area can not be formed.

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According to geological environment, landslids have been classified into three groups: namely, Tertiary Zone, Fractured Zone and Thermal Spring Zone landslides.
Through recent surveys, however, the author has observed that there is a special type of landslide which cannot be included in any typical group of landslide.
The author made investigations of the strata and underground structure, by the earth resistivity method, the strain gage measurement and the boring, and obtained the following results.
1. The landslide movement in Tertiary zone covered with volcanic materials has been conditioned by the products.
2. As the landform due to landslide, the movement is observed at their terminal parts. It is quite different from other landslides in the Tertiary sandstone or mudstone zone without any cover, where the slide can easily happen from upper parts.
There are a little moving blocks with a simple mechanism of motion, while other Tertiary sliding areas have many moving blocks.
3. The landslide motion is slow, begins at the surface materials and shifts to the lower deposits, contrary to that of the sandstone or mudstone zone.

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In the granitic area of the Abukuma Mountains, the writer found “Blockströme (boulder fields) ” and “Felsburgen” in several places. In these places, Felsburgen are usually located at the upper part of the mountain slope and Blockströme are found in the valley flat at the foot of the mountain slope. A Blockstrom at the foot of the Kôdaishiyama (altitude of 500-600 meters), the largest one in these places, is 500 meters long, 10-30 meters wide with the depth of 2-3 meters at least. The slope of this Blockstrom is 5-6 degrees on the average. Blocks in the Blockstrom are generally “Wollsackformen” of 1-3 meters in diameter, but a considerable portion of these blocks is broken with the sharp fracture planes.
In all Blockströme in this region, the present movement is unrecognizable and the running water at the bottom of Blockströme has a tendency to wash away interstitial soil material, resulting in the barren aspect.
It is thought these blocks in Blockströme were transported by means of mass movement from Felsburgen in a recent geological time.
As to the development of Blockströme in this region, in short, three stages are recognized : the first stage is a period of extensive sub-surface rock weathering whose pattern is controlled by structural conditions : the second stage is a period of exhumation by removal of the fine-grained products of rock decay (the appearance of Felsburgen and core stones) and transport of blocks by means of mass movement : the third stage is a period in which interstitial soil material was washed away.

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The writer studied the free meanders in the lower flood plains of the Teshio, the Koetoi (Makubetsu), the Karibetsu, the Yûbestu, the Shokotsu, the Tokoro, the Abashiri and the Musa (Shibetsu) rivers by the analysis of aerial-photographs and topographic maps, and by hydrological data and field investigations. The following points are his conclusions.
1. According to different hydrological and soil conditions, the preceding rivers can be classified into the next two types depending on their free meander forms.
a) In the plains of the Teshio, the Koetoi, the Karibetsu and the Musa rivers the meander rates (ρ) are less than 0.5 (meander rate : = (L-W) /L, where L is meander wave length and W is meander wave width).
b) In the plains of the Yubetsu, the Shokotsu, and the Tokoro rivers, the meander rates (ρ) are more than 0.5.
2. The meander rates of meander scars and scrolls in the flood plains are nearly the same as the preceding meander rates.
3. As the results of the observation on those meander scars and scrolls, these river channels have been shifted toward the back of the loop by cut-offs of meander and slided to the front of spur of each meander loop compensatively.
4. The range of the shifting is nearly equal with the width of each meander belt.

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Remarkable deformation is seen at the crowns of coniferous trees such as Abies Mariesii, Tsuga diversifolia, Thuja Standishi etc. which grow in the subalpine zone above 1200-1400 meters of Azuma, Adatara, Bandai and Zaô Mountains, Tohoku district (Photo. 1). The author surveyed on Mt. Zaô to analyse the relationship between the prevailing wind and the direction of deformation, and concluded that the direction of deformation was in accord with that of the prevailing winter wind.
The results are shown in the distribution maps of the direction of deformation along the ridges of Azuma, Adatara and Banadai Mountains. According to the maps, in Nishiazuma area (Fig. 2) in which the main range extend east and west most crowns are facing northeast, while in Higashiazuma (Fig. 3) and Adatara (Fig. 4) where the main ranges run from north to south and in Bandai area (Fig. 5) which forms an isolated mountain body most crowns are facing east. It should be understood that WNW winter monsoon is prevailing at the upper air in these areas, though near the ridge surface of Nishiazuma area SW wind blows under the influence of the direction of ranges and valleys. Therefore it is supposed that these mountain ranges and valleys cause the divergence and convergence of winter monsoon (Fig. 6) .

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