Many experimental studies concerning sand movement caused by waves have been made in laboratories using water tanks. However, only a very limited number of field studies were made, because of the observational difficulties and complicated factors affecting sand movement caused by waves, rip currents and others.
Considering the results of the experimental studies in laboratories, the auther tried to make clear the actual process of sand movement by sea waves. The study area is situated at the center of the offshore of Tatado coast in Shimoda-shi, Izu Peninsula (Fig. 1). Ten field surveys at the sea bottom were made selecting the various condition of wave intensity (Table 1).
Main results obtained are summarized as follows:
1. With the increasing intensity of waves, the ripple patterns in an offshore station changes from parallel to diagonal, lunate ripples and sand waves (Table 3). This sequence is also observed between the offshore and breaker zone.
2. The process of sand movement revealed by our observation differs from that of expe-rimental results in that the sand movement of traction type occurs in the same extent when the crest and trough of the wave passes over the minor topographies at the sea bottom (Figs. 6-1, 2, 3, and 4).
3. Correlation exists between the wave intensity and the transported amount of sediments, and as Manohar described the rate of the transported amount, G₁ (g•cm^-1 sec^-1) and G₂ (g• cm-2•sec-1), are expressed as a function of the intensity of flow of the fluid near the sea bottom, φ₁', (Figs. 7 and 8).

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Most cities in Japan originated in the feudal days and have developed under the influence of modernization since the end of the former century. It is frequently in evidence that the areal structure of cities differs in accordance with the process of their development. Therefore it is important for urban geography to classify the cities according to the growth and structure of their urban areas through comparative studies. The present writer investigated the process of urban growth and the features of land use in urban area of today taking the example of Sendai, which was a castle town in the feudal days and has developed into the center of the fairly large Tôhoku District. Its population is about 545, 000 in 1970.
In the old castle town of Sendai, the castle area was situated on the western fringe of the town, and the high-class samurai quarter near the castle. The merchants' quarters were allocated in the central part of the town and along the highway. The middle-class samura: quarter occupied large areas around the merchants' quarters. The periphery of the town was composed of the temple quarter and the lower-class samurai quarters.
Because of the social changes after the Meiji Renovation (Restoration) of 1868, the resi dential areas of the samurai class were deteriorated and in the outskirts, turned into agricultura. land. The castle area, other areas belonging to the feudal clan, and the high-class samura quarter changed to the sites of new government offices, schools and the military spaces. Orr the contrary, the merchants' quarters remained mostly untouched in their former location. Along the central shopping street banks and public institutions were built.
After the construction of railway in 1887, the central commercial area expanded towarc the station and public offices and schools were added around it. Although some schools were built in the outer part, the abrupt expansion of urban built-up area did not take place. House: soon built at that time were mostly located around the central area where many vacant spaces were seen. So, an increase in the density of houses within the extent of old castle town was recognized. Such urbanization kept on until World War II. In the 1930's some schools, hospi tals and factories were built beyond the built-up area, and several housing estates were con structed by the municipal and prefectural governments.
In 1945, the central part of the city was destroyed by the air raids. According to the cityplanning after the war, main streets in the damaged area were much broadened. Housing estates by the municipal and pref ectural governments and other establishments newly built in this period were arranged on the northern and southwestern hill-lands.
After 1955, new housing suburbs were added on the hill-lands and eastern flat area in accordance with the increased population. On the eastern fringe industrial estates and distri-bution centers were constructed outside the new residential area. In this period, a number of recreational and educational establishments were removed from the old urban area to the west-ern hill-land. In the central business district large buildings have been constructed, and func-tinoal differentiation of streets is now in progress. The area around the CBD is dense residen-tial sections, since the area escaped the destruction of the war.
As a result of the above-mentioned growth, the urban area of today is composed of various quarters characterized by different functions and formed in different periods.
1) Central business district. In the commercial areas, stores, banks, business offices, etc. are concentrated. They are composed of the old commercial quarters in the former castle town of the Edo period, and of the area newly developed after the construction of railway station.

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Quantitative representation of the erosional stage of landforms is attempted by means of HRT (Relief) diagram. It is necessary for construction of the diagram to obtain the rela-tive height of ridge and valley floor as well as their difference (relief) to the available relief which can be calculated by substracting elevation of channel floor from that of summit-plane. Based on these values, any erosional topography is represented by a point in a triangular diagram named HRT (Relief) diagram. Stage or relative age of the topography is given quantitatively by the position of the perpendicular on the base-line of the diagram.
An application of the diagram was attempted for a hilly land to the east of the River Kako in Hyogo Prefecture, Japan. It is known from the result that almost a quarter of the whole volume has been removed by erosion. Assuming the age of Meimi gravel to be ca. 300, 000 years B. P., denudational rate of the hilly land is found to be 0.08mm/year, which is acceptable compared with the rate known for other regions by other methods.

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The W-NW winds from the Japan Sea prevail in the Ishikari Plain in winter and the S-SE winds from the Pacific Ocean in summer. In order to make clear the detailed distribu-tion of such prevailing winds, the writers observed the wind-shaped trees at the 180 points as indicators of wind speeds and directions. The wind-shaped trees observed were those of Fraxinus mandshurica, Alnus japonica, Larix leptolepis, Populus spp., Picea jezoensis etc. and the grade of deformation was determined as illustrated in Fig. 1. The results obtained are summarized as follows :
(1) In summer (Figs. 2 and 3): (a) The southerly winds from the Pacific Ocean go up to north in the central part of the Plain along the Yubari mountains and then gradually change the direction to northeast wards between the Mashike mountains and the eastern moun- tain regions. (b) One branch of the southerly winds flows northwestwards from the central part of the Plain to the Japan Sea. Another branch flows into the low land area around Yuni between the Yubari mountains and the Umaoi hilly region. (c) The strongest wind region was found in the area arround the City of Ebetsu, the central part of the Plain. The other, small, strong wind regions were distributed in several parts, , as caused by the local topogra phical conditions.
(2) In winter (Figs. 4 and 5): (a) The northwesterly winds, the winter monsoon, prevail over the Plain. Their southern border was located at Ôyachi, but the eastern border runs fur-ther inner side along the foot of the Yubari mountains. (b) The westerly winds, after crossing over the Mashike mountains, change their direction slightly and blow northeastwards between the Mashike and the Yûbari mountains. (c) It was confirmed, from the distribution of remain- ing snow on May 1_??_6, 1970, that the so-called local “Ishikari-front” runs roughly along the line connected from Tôbetsu to Iwamizawa, as shown in Fig. 6.
(3) The results mentioned above were compared with the results, given in Figs. 7 and 9 for summer and in Figs. 3 and 10 for winter, which were observed instrumentally at the 20 Agrometeorological Stations distributed in the area studied. A striking good coincidence was seen for the conditions of southerly winds in summer. Of course, the distribution map obtained by observing the wind-shaped trees revealed the detail, because of the number of observation points. For the conditions in winter, however, it is considered that the prevailing wind conditions estimated by the wind-shaped trees of ever green needle trees such as Picea jezoensis do show the distribution of the winds with snow. Therefore, it can be said that the winds carrying snow are the prevailing winds in winter in a broad sence, but they are not always the most frequent winds in some places.

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