There is a stringency about the existance of periglacial activities in some districts of Japan from the last glacial stage to recent. Some amounts of studies on periglacial pheno-mena relative to both fossil and recent types have already been made, and a few attempts were carried out to outline the palaeoclimatic zones or palaeogeographical features of Japanese Islands during the Würm stage using some data indicating palaeoclimates by field observations about fossil patterned ground and other features distinguished as periglacial phenomena.
While the concept that patterned ground indicates the palaeoclimate or palaeogeography has been accepted, there remained some confusions between terminology and genetical ideas about patterned ground in Japan. So, it was hoped that from the viewpoint of genetical ideas, re-checking of patterned grounds might provide profound data for palaeogeography, if the works would be carried out without confusions.
In this preliminary study, the authors did on-the-spot investigations at such mountains as Mt. Kamikochi (2803m) and Mt. Chausu (2600m) in the Southern Alps and Mt. Kaun (1954m) of Taisetsu Volcano in Central Hokkaidô. After these field works, we analysed the observed data and materials, and discussed on genetical ideas and environment, under which these patterned grounds develop.
Conclusions are summarized as follows:
(1) According to Washburn's classification of patterned ground, the patterned ground we observed is classified as “sorted circles” from its morphological feature, and there are two groups of different sizes, diameter 10-15cm and 100-150cm.
(2) The places where sorted circles develop are fiat or gentle slopes covered with weathe-red debris without vegetation covers, or some depressions formed by snow patch erosion and dammed up shallow valleys. Larger size sorted circles develop at the bottom of depressions, which are sometimes filled with snow-melted water during summer and also with weathered materials from bedrock. The altitudes are usually around 2, 500m in the Southern Alps, and around 1, 600m on Mt. Kaun in Hokkaidô. In these areas, the altitude is above the timber-line and nearly the some with the zone of pines montana.
(3) The observations of soil profiles of sorted circles show two stratified layers, coarse sand and debris for the upper, fine well sorted sand and silt for the lower. The boundary of these two layers is sharp and not horizontal but waved. Careful taking off of the upper layer enables one to observe the three dimensional forms of the boundary, and it shows the exi-stance of mound-like forms. There is an obvious relationship between this mound form and sorted surface features. The center of sorted circles consisted of fine materials coincides with the top of the peak part of mound form. The fringed contour of sorted circles consisted of coarse materials concides with the outskirts of mound. So this mound form controls the size of sorted circles.
(4) There are no fissures and no sand wedges which cut deep the fringed contours of sorted circles. But the mound form of boundary shows the process that the lower fine sand and silt layer extrudes into the upper coarse sand and debris layer without developing fissures.
(5) The features of sorted circles mentioned above support the idea by A. E. Corte, that is, by the multicycles of freeze-thaw, the lower fine material layers extrude into the upper layers, and this differential movement of particles forms the mound form. The depth of lower fine layers, termed as active layer, controls the size of sorted circles. By other mecha-nical sorting processes, the surface sorted circles will develop.
Of course, it is hard to explain all processes and mechanisms of sorted circles by restricted genetical ideas, but the further advanced fieldworks and laboratory methods are hoped to be carried out in some areas distinguished as periglacial regionss in Japan.

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Calms or breezes are very important to understand air pollution, especially from the viewpoint of the potentiality of spontaneous clarification of atmosphere itself. Little has been studied on calms or breezes, nevertheless many climatological researches have been done on-gales, storms and damages caused by them. This paper intends to make clear (i) the rela-tionships between calms (less than 0.5 m/sec) and atmospheric stabilities in the Ichihara area, Chiba Prefecture, (ii) geographical distribution of calm-ratios (percentages of calm-frequency to total observations of wind), and (iii) explanation of some causes of calm.
The results obtained are summarized as follows:
i) The diurnal variations of calm frequencies and atmospheric stabilities are shown in Figs. 1 (a) and (b) for winter and in Figs. 1 (c) and (d) for summer. In general, calms occur very frequently from late evening to early morning when the atmospheric layer is stable ; namely, in the case of temperature inversions or smaller lapse rates. This tendency is remarkable in winter. Although Ichihara faces Tôkyô Bay, the dawn calms are not so indistinguishable because there is no obvious exchange of sea and land breeze.
ii) The annual fluctuation of calm-ratio was compared with that of inversion-ratio in Fig. 2e The latters mean percentages of inversion frequencies to whole measurements of ver-tical air temperature. The correlation coefficient between them is fairly high (0.749) and the regression curve is expressed as
I=0.80C-0.86
where I and C are inversion-and calm-ratio respectively.
iii) Tables 1_??_4 show the relation of calm-ratio to inversion-ratio mainly using the data S for Sendai, Miyagi Prefecture. It can be seen that both calm and inversion decrease with increasing altitude as the annual mean conditions, but calm-ratio at the 1000m-level in sum-mer is comparatively larger while inversion ratio at the 500m-level in spring and at 1000m in summer are rather greater than at the surface-level. With respect to the daily variation, calms appear more often at the 1000m-level than at the 500 m-level and the surface-level. In short, the atmosphere over the urban area very frequently shows a higher calm-ratio than the surface-level, which is also confirmed by the vertial distribution of SO₂-concentration, etc.
iv) Local phenomena of geographical distribution of calm-ratio are discussed in order to verify the influence of surface friction to the wind. Twenty-four maps in Fig. 3 present the horizontal distribution of calm-ratio in the Ichihara area. Generally speaking, calm-ratio (C) decrease as the distance from seashore increases. Thus the following equations are obtained:
For winter (January, 1967 and 1968),
C=4.5D+14.1 and
For summer (July, 1966 and 1967),
C=2.7D+20.1
where D is the distance (km). In Fig. 5, the relations of winter half-year are shown. The initial conditions at the coast (D=0) are larger in summer than in winter while the regional differences are smaller in summer than in winter.
v) Geographical distribution of calm-ratio in Japan is given in Fig. 6. It is evident that the calm-ratio is smaller in coastal regions and larger in inland areas particularly in basins. As exceptional cases, the regions facing the inland seas or bays have large calm-frequencies.

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1. For a decade starting 1955 the Japanese economy achieved an extremely high growth, at a rate unparalleled by the economies of other advanced nations. On the reverse side of the coin, however, this high economic growth stimulated the sudden and large-scale influx of industries and population into big cities, and, bacause of the failure of social overhead capital to catch up with the needs, it has given rise to various urban problems.
In the composition of Japan's fiscal expenditure, the ratio of the defense expense is ex-tremely low as compared with other advanced countries. In contrast, the ratio of the public works expense (investment in social capital) is relatively high.
Such investment in social capital, however, has so far placed top stress on the strengthe-ning of the industrial foundation to the relative naglect of the expansion of the living founda-tion based on housing and other living facilities. Without this policy and the movement of population from agricultural villages to cities, the present prosperity of the Japanese economy is about to enter the stage of stable growth after a brisk expansion in the 1960s. 2. The advancing rate of land prices in the six major cities has kept pace with the fluctua-tions of the economic growth tempo. During the previous two business boom period, land prices soared markedly. In the process of the current business upswing, the increasing pace of land prices also has been accelerated.
As the economic growth rate in the next five years is likely to stand strong incentive in the demand phase. As such, more drastic steps are supposed for curbing the advance of land prices.
The residential districts in the Tôkyô Metropolitan Region have been developing clockwise from the southern and western parts. In comparison with the rapid advance of land prices in the western parts (Mitaka, Musashino, etc.), the land prices in the northern and eastern parts (Koshigaya, Matsudo, etc.) continued to stay relatively lower until a few years ago. However, the prices of land in the northern and eastern parts have begun to soar along with the progress of motorization and the advance of land prices recently.
3. Urayasu in Chiba Prefecture is situated to the east of Tôkyô, but has not been urbanized as it is difficult in accessibility. It has a population of about 20, 000, its soil is not good for agriculture. Its economy, therefore, has depended on the coastal fishery and nearly all its people have been engaged in agriculture and fishery for livelihood. But urbanization has attached in wave to Urayasu, owing to the opening of the subway connected to the heart of Tôkyô at the end of March, 1969.
4. Judging the phenomenon of urbanization of Urayasu from such angles as diversion of agricultural land, starting construction work and vital statictics, we can recognize the great difference both in quality and in quantity from the end of 1967, 1968 and 1970 respectively.
The farmers of Urayasu are very petty peasants compared with those in her neighbouring cities and towns, and 80 per cent of them do not sell their crops at present. Since the sub-way plan connecting Urayasu with the heart of Tôkyô was announced in 1965, the residential land price has shot up.
Fishery in this place has been inactive due to llreclamation work of the foreshore, land readjustment work giving impetus to this situation, so that the farmers who sell their farm land or build and manage the apartment houses on their farms increased in number. This tendency has spectacularly increasedd in number since the end March, 1969, when the new subway was opened for traffic.
5. Residential land price at Urayasu has gradually risen since about 1962, and has reached 120, 000 yen per 3.3m² after a jump in 1968-9. But since then the price has been following a crablike course, showing the aspect different from general cases.

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This report deals with some results of the restoration works for the ancient paddy field pattern developed by the jôri System, a grid-pattern land development, in the northern part of Ibaraki Prefecture. Restoration work was accomplished by means of tracing the forms of the land partitions for paddy fields developed by the jôri System in relation to topographies. The form of these partitions was assertained by referring to the land-register maps with the aid of topographical analysis by on-the-spot investigations chiefly relying on soil maps.
The survey reveals that, in the lowlands across which the River Kuji runs, there are orderly laid-out paddy fields by the jôri System and many of them are located in backmarshes. Ancient paddy fields with this system were successfully restored on the left side of the River Asa by referring to the old land-register maps available, while most paddy fields there were displaced by the land readjustment enforced in 1909.
It may be said that there were not many gridiron fields of the jôri origin in the lowlands along the River Naka. The facts that the scope of the jôri System paddy fields is quite limited on the right side of the Naka and that the pattern of field network is irregular on the left side are in contrast to the studies by others. Attached maps will show these facts.

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Report read at the symposium on Applied Geography in General Meeting of the Association of Japanese Geographers in Tokyo on 4th April, 1971. Translated by Hiroshi TANABE, Professeur â l'Universite de Tokyo.

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