The effects of the distribution of land and sea on snowcover and direction of snowy wind in a coastal region is of striking interest in the local clizma tology of snow. The author attempted a survey in an area of about 20 square kilometers bordering Tokyo Pay. (Fig. 1)
(1) As snowcover and terrain very from plane to place, it was necessary to determine an accurate method of snow depth measurement. For this purpose, special concideration was taken, as in Fig. 3; results are shown in Table 1. When the depth of snowcover is less than 30cm, the mean value for 5 measurements at a place have a variance of ±1 cm at the maximum and test results show that the values of 5 paints on a starlike line have a smaller variance than those on one straight line.
(2) To determine the average depth of snowcover in this area, observa-tions were made early in the morning of Feb. 22, 1953 covered with snow which had accum ulated since the morning of Feb. 21st (Fig. 2). Results of these observations are shown in Fig. 4. .Depth is represented as a linear function of the logarithm of the distance from the coastal line, that is: y=a logx+b_??_ (1) wherex: depth of snowcover in cm, Y: distance from the coastal line in hm, a, b: constant.
In this case a=11.49, b=1.09.
(3) Applying the data accumulated at the 10 weather stations in this area, the value of the constant a in equation (1) was calculated fur each of 20 cases. As is shown in Table 2, a is positive with but one exception. This means that the snowcover, in general, increa=yes in depth with the distance from the coastal line. It maybe explained by the effect of diffe-rences in air temperature and wind velocity between the seaeoa dt and inland points.
(4) The constant a is not related to the depth of snowcover, but rather to the length of the duration of snowfall. The exceptional cases seem to be related to the influence of the front remaining at the eoast and bringing frontal snowfall for a relatively long period. The experimental equation is a=0.36 t-0.12_??_(2) where a :constant in equation (1), t: duration of snowfall in hours. In theoretical considerations, if t becomess 0, a must be 0, and practically the second term is smaller than the first _??_because t must be greater than 4 (hours), the shortest time studied in this paper_??_. Therefore, as the second term is negligible, it can be approximated as: a=0.36t_??_(21) Then, y=(0.36t) logx+b_??_(3) where y: depth of snowcover in cm, x: distance from the coastal line in hm, t: duration of snowfall in hours, b: constant determined by meteorological conditions in each case.
(5) The prevailing wind direction during the snowfall was also observed at 136 points in the morning of Feb. 22, 1953 by utilizing the fact that when air temperature is near 0°C, falling snowflakes tend to adhere to the windward surfaces of electric poles and tall chimneys. Result s, as shown in Table 3, indicate the prevailing snowy wind direction to have been N y NAT at the inland stations gradually turning to I at a distance of about 8 k ml from the seaccoast where it is almost due N. This is considered to be a result of the difference in the time of snowfall occurrence as affected by the different air temperatures. in this area or of the difference of friction at land and sea.

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Among the advantages of bus service it is held to have a small unit of, carriage and great flexibility. However, the bus is at a disadvantage (both in cost and speed) where traffic is heavy. Oku-izu, the southern part of Izu peninsula, is a mountainous district in which traffic is rather light, but, since there are no railways, bus service is comparatively well utilized there (Fig. 1).
The writer has studied bus transport of the inhabitants of Oku-izu. Fig. 2 shows the monthly frequency of trips by bus per family in each community. There are two “ordinary regional centers” (the fourth order) and several “service villages” (the fifth order) according to F. H. W. Green's classi-fication. The centers of the fourth order are Shimoda and Matsuzaki. Pas-sengers carried by bus converge on these towns. In order to analize this phenomenon, the writer adopted the following formula
_??_
Fig. 3 shows the rates of convergence for Shimoda and Matsuzaki. The relationship between the frequency of convergence and the distance to the centers are shown in Fig. 4. The following formula may be deduced: y=ax-b, where y=frequency, x=distance (kin), and a=?. In the surround-ing area of the centers, the value of (b) has been determined as
Shimoda…… b=-0.91 Matsuzaki……b=-0.27; and in a remote area, Shimnoda……b=3.32, Matsuzaki……b=-1.73.
In a mountainous region such as Oku-izu, the application of the PA RETO-equation must be divided into two parts: One should be applied in the district surrounding a center within which the rural-urban interaction is strong, while the other should be applied in remote districts where such interaction is weak.

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[in Japanese]

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This paper is a preliminary report of the landslide in the southern part of BOSO Peninsula at Soro Village.
The landslide of Soro Village, situated 6 km., west of the town of Kamo-gawa, occurred on May 23, 1952 near the top of Mineokn Mountain and gradually enlarged and extended itself down the slope.
The mechanics of the landslide may be explained as follows
1) The serpentine was distributed in the vicinity of the divide of Mineoka Mountain and was weathered in depth. When a great amount of ground-water percolated into weathered materials, they were generally liable to slip. Landslips of the serpentine have occurred on the upper part of the slope so that a great deal of debris was accumulated there.
2) The materials of the landslide consisted of rock debris and clayey soils derived from serpentine. This debris was weathered by percolating water and became a clayey soil colored white-blue. This clay had a very low liquid saturation point (Tab. 1.), hence, it was liable to slide. On the other hand, stationary earth materials generally were found on gentle slopes composed of sandstone, greywacke and shale (Mineoka group); their soils had a relatively high liquid saturation point (Tab. 1) and have resisted slides.
3) There are paddy fields on the upper part of the slope and corn fields below. Hench, groundwater from the paddy fields also percolated into the debris.
4) The temporary increase of pore water pressure, which lead to a disa-strous reduction of internal frictional resistance, may be considered as another of the causes of the landslide. The determinations of the depth of the slip plane, the shearing strength of creeping materials, and of the chemical changes of serpentine will be necessary for the continuance of studies on the mechanics of the landslide.

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