The author has measured the bending direction of top-twigs of persimmon trees at the Akaho Fan which occupyes an area of about 25 square kilometers in Nagano Pref. in Japan.
(1) The b_??_n_??_ing direction shows the prevailing wind direction at each place during the period about April to June, the growing season of persimmon trees in this region.
(2) The reliability of such measurements are about 15°.
The author and his collaborators have made such measurements at 230 places. They could obtain following results:
1) The southerly wind prevails every where on the fan surface in early summer.
2) But precisely speaking, its direction is affected by the valley shape of the Tenryu River in this region. Its direction diverges where the width of valley is broad, and it converges where the valley is narrow.
3) When the wind meets some obstructions, it generally changes its direction toward. the right.
4) In the valleys which cut in the fan surface, the blowing direction of prevailirg wind. is different from that of the fan surface above:
a) In shallow and small valleys, wind blows up along the stream.
b) In deep and large valleys, the prevailing direction of wind changes utterly. It prevails the wind opposite to that of. the fan surface caused by ddy turbulences.
5) We can find a wind shadow area which has about 250m width below the steep escarpement bordering fan surface towards present flood plain. Here it blows a week wind toward the north.
6) These local wind directions estimated by the bending direction of persimmon top-twigs coincides well with the observation of wind directions on some days when the soatherly wind prevails on the fan surface.
7) The effects of surface covers, villages, forests etc., can not be recognised clearly in this case.

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The yield per unit area, as an indix of the agricultural productivity, fluctuates annually and changes in different regions according to the economic and physical conditions.
In this paper, I have tried to clarify the relations between the yield of rice and the climatic conditions in Tottori Prefecture, for which purpose, I have tried to leave out economic factors reflected to the yield as production functions.
By a statistical method, dealing with the figures of 27 years from 1911 to 1937, I have calculated the ratio of the rice yield per unit area (tan) showing its yearly changes in prefectural average. This ratio is prepared as an important basis, of the fluctuation of the harvest for study of the relation of climatic elements to the rice yield.
Using the mean temperature, amount of precipitation and sunshine measured at Sakai Meteorological Station, I have computed the correlation coefficients between their yearly changes in each month or in several months and the ratio of rice yield. The results obtained are shown in table 1.
The correlation between monthly mean temperature, sunshine and the rice yield is positive during the growing season, especially its relation is remarkable in 4 months from Junee to September, which is the active growing period. The relation to precipitation is negative, which is marked especially during period excepting that of rice transplanting.
The correlation coefficient between the total amount of monthly mean temperature in 4 months from June to September and rice yield, is +0.536. This total amount of temperature in 4 months is important for rice culture.
The correlation to the total amount of the precipitation in May, July (exeluding the first ton days), August, September is remarkable. Its correlation coefficient is 0.571, if the years of damage from storms and floods within these 27 years are put out of consideration. If such years are included, the coefficient becomes -0.673.
Neither the correlation to the mean sunshine in 5 months from May to September, nor in 3 months from July to September are marked. The above described correlations show us that, in the combination of two climatic elements-the total amount of temperature in 4 months from June to September and of precipitation in May, July (excepting the first ten days), August, September-T_??_-type, or high-temperature-little-rainfsll type, is sui-table forr rice culture; whereas _??_P-type, or cool-temperatuure-hcavy-rainfall-type, causes a complete failure of crop. This relation is plainly shown in Fig. 2.
The multiple correlation coefficient between rice yield and these two climatic elements becomes 0.785, which shows a notable correlation.
To study the difference between plain and mountainous districts, I have calculated by the same method the correlation coefficient in each landscape, using the climatic data at respective observatories. The results obtained are shown in table 3.
To precipitation, the negative correlation is more remarkable in mountainous districts than in plains, while the positive correlation to temperature is heavier in plains than in mountainous districts. Fig 3. show that the bumper crop is made sure by the amount of temperature over 95°c C and the precipitation below 600mm. In a condition over 95°C in temperature and below 600mm in precipitation, rice yield rises in porportion to temperature. Fig. 4. show this positive correlation.

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The writer has investigated some characteristics of Urawa City (Saitama prefecture) as one of the satellite cities that develop around the metropolis Tokyo. The results may be summarized as follows;…
1. Urawa has been a small local town untilrecent years, but lately it became rapidly to be joind with the res dental district of Tokyo, in accordance with its expansion. By the destruction of Tokyo in this war, the population of Urawa increased snore rapidly.
2. The citizens of Urawa are closely tied together with Tokyo ha their daily life, majority of there working, shopping and amusing themselves there.

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