Geomorphologists in Japan have attempted to explain geomorphologic history on an assumption that the Japan Islands were flattened in late Pliocene or early Pleistocene age. This idea supports a hypothesis that the outlines of landscape in Japan can be safely explained in relation to tectonic movement in Pleistocene age. Traces or relics of erosion surfaces represented by undulating low relieves of summit and accordance of ridge are distributed partly to sparsely almost all over Japan. So they have been regarded as an evidence of realization of planation covering Japan. The author objects to this hypothetic view, because we have not had satisfying information yet on duration needed for planation or reduction of mountain. Unfortunately, it is very difficult in Japan to reconstruct the past landscapes because of overlaping tectonic activities. Concerning this problem, the author could obtained suggestive informations from continental mountains in view of morphotectonics as C. D. Ollier and his group members suggests. The author introduces the geomorphologic development of the eastern high lands of Australia and continental mountains or Great Escarpments in some other area studied in morphotectonic view. Morphotectonic studies of continents suggest that mountains in humid temperate region do not reduce so fast as they have been expected in Japan. The author is again convinced of an idea that the landscape in the Japan Arc involves relics and remnants of old relief formed by tectonic movement in Miocene or Pliocene age, or probably in early Tertiary age. It can be safely assumed that almost erosion surfaces in Japan may be dated back to early Tertiary or older time. But it is unfruitful to discuss of their age or origin, because we have scare data concerning with them. Finally, it is proposed that the researches as follows are needed before we discuss of evolution of mountains of Japan. 1) Miocene volcanic rocks which have not been thought to be dissected enough to remained in outlines of original form, should be examined to reconstruct their original forms. 2) Mountains and highlands which have been thought to be uplifted uniformly in Pleistocene age, should be rexamined to make clear chronological order of uplift. 3) Development of drainage systems in Japan which have been rarely a matter of concern, should be researched in relation to multiple tectonic movements. 4) Miocene sediments which have not been studied in relation to surrounding landforms, should be attempted to reconstruct directions of streams and landforms.

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In geography, there are two viewpoints in analyzing the spatial structure, those are, homogeneous regions and nodal regions. Many studies up to now are analyzed it from these viewpoints. This paper aims hirstly to investigate the structural characteristics of homogeneous regions based on socio-economic variables and that of nodal regions based on work/school-trip flows, secondly to clarify the change in homogeneous regions and in nodal ones from 1960 to 1980, and lastly to examine the inter-dependency between the two structures with the framework of Berry's general field theory. Hokuriku district, composed of Toyama, Ishikawa, and Fukui prefectures is chosen as the study area. Three prefectures in Hokuriku District are recognized as one region which the socio-economics activities and work/school-trip flows are united. Reserch units in this paper are legal cities, towns, and villages. The results of analysis are summarized as follows : 1) In order to clarify the change in the homogeneous regions in Hokuriku district, the statistical data of 48 variables for 111 unit areas were arranged into the 111×48 matrix in the periods of 1960 and 1980. Factor analysis was applied to the 222×48 matrix which was produced by merging the two matrices in 1960 and 1980. As the results of this analysis, four factors accounting for 66.8% of the total variance were extracted, those are, socio-economics status (40.16%), urban hierarchy (14.48%), suburbs (6.9%) and depopulated areas (5.12%). The scores of the 1st factor were all negative in 1960, on the other hand, were all positive in 1980. It was shown definitely by the factor scores that the socio-economic status of the people were remarkably raised during 20 years. The distribution of the 2nd factor score showed in the plain area with high values and in mountain villages with low values. And the scores of the factor 4 were in contrast with the factor 2. In the spatial arrangement of the 3rd factor scores, concentric patterns were distinctly recognized. 2) The work/school-trip flows were synthesized by Q-mode factor analysis with 21 regions in 1960 and 17 regions in 1980. The principal destinations of the 1st, 2nd, and 3rd factors in each period were the prefectural capitals. Medium ranking factors were expressed by the flows to the sub-prefectural capitals, and lower ranking factors indicated the local flows. In comparison with factors extracted in 1960, the 1st, 2nd, and 3rd factors in 1980 augmented their percentage of the total variance. 3) Using the Canonical analysis, the interdependency between the homogeneous (socio-economic) and the nodal (work/school-trip flows) regions were confirmed. Two canonical variates were extracted. Inter-pretations of them are sumarized as follows : 1, the work/school flows to the cities that have a high central function and the high wholesales activity were come from peripheral cities, towns, and villages within the Fukui, Toyama, Komatsu, and Kanazawa spheres. 2, The city with locai central function such as Tsurugimachi has not a high wholesales activity.

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