The population difference between day and night in Japanese cities were first increased in big cities in the boom soon after the World War I. The increase of population was specially obvious in Tokyo after the Great Earth-quake of 1923. After the World War II, owing to the war-damages and some other reasons, almost the same results have been apparent in local cities. Namely, the population difference between day and night in the cities acid their commutation area have been more eminent after the war, compared with those of pre-war Japan.
The population difference between day and night in Tokyo, Osaka, Hiro-shima and some other cities was observed and the following results were obtained.
(1) Except those cities which receive daily sightseeing visitors, about 70_??_80% of the moving population in daytime is regular from rural districts to urban.
(2) Of the whole moving population of a city between day and night, the inner moving population is larger than the outer moving population, whose difference is increased 4 according to the extension of city area.
(3) The moving population between rural districts and urdan (the outer moving population) is small in number but the moving distance is farther, which imposes on us future considerations in regards, to preventing the fatigue and physical disorders of the commuters including students.
(4) The regular moving population in daytime was observed according to the means of traffics and the kinds of the works they concern. The mental workers were predominant and there were more men than women in number. (Table 1)
(5) The commutation area of the large city population between day and night is larger than the small city, but in local cities, its. commutation area has been larger since the end of the war. (Table 2. Tokyo)
(6) It is not so different from the case in a pre-war city that the recent commuting area of the city population between day and night is about 30km which takes about one hour to cover. (Fig. 1. Osaka, Fig. 2. Hiroshima)
(7) Therefore, it may be concludedd that the first limit (the Inner Suburbs) is within 30km and the second limit (the Outer Suburbs) is over 30km to 60km from the city center, and over 60km can be considered to be out of the sphere of daily city lives.

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Along the shoreline of Lake Nojiri which is located among the volcanoes at the northernmost part of the Fuji Volcanic Zone and the upper course of the River Torii, there is noticed the distridution of lacustrine terraces that are separated by a low divide at Kumagura (Fig. 1).
The writer observed at Furuma the fossil lacustrine terrace which contains a considerble number of lacustrine diatom fossils (Fig. 2, Tab. 1). The change of these fossil species in the stratal parts from A to C suggests that the old lake had been gradually filled up, and the peat bed of D containing Eunotia pectinalis seems to indicate the deposits at the shallowest stage of the lake. However, the occurence of clay and of fossils such as Synedra ulna and Gomphonema parvulum in E and F likely show that the lake level had relatively risen.
Topographically to say, the middle course of the River Torii flows down through the mudflow district (Fig. 3). It is regarded that these lake deposits made the present topography resulting as overflow of lake water and that the Palaeo-lake level of “Furuma Fossil Lake” was about 675m above sea level.
It is presumable that this fossil lake was a part of “Palaeo-lake Madarao” at the age of deposits of A-D in the Furuma fossil terrace and that the River Torii supplied much water to, that lake, judging from the topography in which the ancient outlet was so deeply dissected against the poor inlets on the present-day shore of Lake Nojiri. Considering from the altitudes of the ancient outlet, of the old shoreline and of the peat deposits, in that age the level of “Palaeo-lake Madarao” might have been about 665 meters. After that time the “Palaeo-lake Madarao” might have been separated into two parts at Kumagura by the Nagahara lava flow. One of them became the “Furuma (Fossil) Lake”, the level of which then rose and overflowed as the River Torii, and another became the “Palaeo-lake Nojiri” that changed its outlet as the River Ikejiri in a later stage (Fig. 4).
Therefore, present-day Lake Nojiri may be considered as a remnant of both lakes of “Palaeo-Madarao” and “Palaeo-Nojiri”.

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The writer has surveyed the glacial topography of the Tateyama Range in the northwestern part of the Hida Mountains, the lava plateau of Tateyama Volcano (Fig. 1) and the river terraces (Fig. 2) along the upper stream of the Joganji River. The results may be summarized as follows.
(1) The gravel beds of Awasuno and Ashikuraji terraces (Fig. 3) were deposited After Midagahara lava plateau had been formed (Table 1) and the western side of the crater wall had been almost destroyed -by breakdown and erosion.
(2) The explosion of the Mikurigaike took place after Midagahara lava plateau had been formed, was an event in the latter half of Tateyarns ice age (=Hida ice age) which may be correlated to Würm ice age.
(3) In the gravel beds of Chigaki and Yokoe terraces (Fig. 4) huge boulders can be found, while in those of higher and older ones of Awasuno and Ashikuraji they can't. Comparing the gradient of the present river-flow with those terraces, it may be said that those gravel beds were deposited by the increse of the river-water. The writer has concluded, therefore, it was probably at ice age or its melt-water stage that these gravel beds were deposited.
Basing upon the facts as stated above, the writer has mad the chronologi-cal table of the geomorphological development of the area treated (Table 2).

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