The author collected samples from two regions, Kutchan and Urawa, where both soils are considered to be derived from volcanic loess-a sort of fine volcanic ejectas. Although the each profile seems to have a very thick monogenetic profile at a glance, but the soil profiles are made of some piled layers. The soil near Kutchan is called to be derived from the ejectas from Mt. Yotei but the latest ejectas from that volcano consist of pumice gravel, pumice sand and scoria etc.. including only thin layers of loamy materials, and they are different from the objective soil which only developed on terrace like "Kwanto loam". From the observation of the soil profiles and the results of the analyses of particle distribution and the investigation of the mineral composition, each profile is made up by some different layers. The soil of Kutchan is composed of three layers but morphologically it could be devided into four horizons, and the soil of Urawa is divided into six horizons from the top to the depth of about 250 cm, but it seems to be composed of five layers. The chemical and the clay mineralogical analyses of the Kutchan soil were carried to know the direction of weathering. The composition of clay minerals of Kutchan soil is high in allophane with some kaolin and 14Å minerals. The composition is similar to those of the Kwanto loam. But the acidity of Kutchan soil is very high, as compared with that of Urawa. In spite of the difference of parent material, the directions of weathering of both profiles are very similar and the Kutchan soil seems to belong to an Acid brown forest soil and the Urawa soil to be a Brown forest soil.

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In view of soil bio-climate, the Japan South Alps or Akaishi Mountains is situated in the humid marine climate region of the northern subtropic zone. With an increase in altitude from Paleozoic hilly terrain along the Lake Hamana to the main ridges, a series of vertical zonality of soils was found, and summarized as below. 1. The foot region of the Japan South Alps, below 500 m in height, consists of subdued Paleozoic terrain. The climate is northern humid subtropic, and the region belongs to the colline zone (TAKEDA, 1957). Under evergreen broad-lieved forest of Castanopsis cuspidata SCHOTT var., Sieboldii NAK., Cyclobalanopsis, and under its regenerated forest of Pinus deusiflora SIEB. & Zuco., develop Red-yellow soils (KANNO, 1961) on Paleozoic slate and relict red weathering crust. Their genesis is characterized by kaolinization. The region is located in a transitional zone between the Brown forest soil region under the humid temperate climate and the Red soil region under the middle part of the humid subtropic climate. 2. The maturely dissected foreland region of the Japan South Alps, with the altitude of 1,000 m, belongs climatologically to the marine humid temperate and plant-geographically to the montane zone. Under broad-leaved forest of Fagus crenata BLUME, Quercus crispula BLUME, and Quercus serrata THUNB., and under artificial forest of Cryptomeria japonica D. DON and Chamaecyparis obtusa ENDL., are formed Mountain brown forest soils on Mesozoic and Tertiary slate rocks, the genetical character being influenced by siallitization. The soils are more severely leached than RAMMAN'S "Braunerde", so regarded to be the Base-unsaturated subtype of the Brown forest soils from the degree of leaching (FRIDLAND, 1953). A weak podzolization of this soil is found in the upper part of the montane zone. 3. North of the foreland region follows dissected mountains of high relief represented by the main ridges of Japan South Alps. Slopes of the mountains with the altitude of 1,500 m to 2,600 m lie within the sub-alpine zone of the humid subboreal climate. Under coniferous forest of Abies Veitchii LINDL. and Abies Mariesii MASTER, there are Podzolic mountain brown forest soils, or Podzolized subtype of the Brown forest soils (FRIDLAND, 1953) on Mesozoic slate. Partially Alpine iron humus podzols with a distinct bleached horizon, A_2, are also found. In the upper part of the sub-alpine zone approximate to the forest limit, Alpine humus soils are formed under herbaceous vegetation of Gramineae and Cyperaceae, among sparce trees of Betula Ermani CHAM. 4. The main ridges of Japan South Alps above the timber-line are included in the alpine zone of periglacial or subnival climate. Piuus pumila REGEL is dominant species in this zone, and alpine grass covers small areas. One can find Alpine podzols with a distinct bleached horizon, A_2 and a well developed illuvial horizon, B_2. The soils are very gravelly, and solum, in most cases, being thin. Within the alpine grassland, Alpine humus soils under herbaceous vegetation with shrubs are found. The soils have similar characters to those of the subalpine zone, except the tendency to weak podzolization. Since Alpine iron-humus podzols and the Alpine humus soils coexist in a mosaic pattern within the same zone without any regularity or zonality in Japan South Alps, the Alpine humus soils concerned should be distinguished from similar soils found in European and American alpine grassland zones where the Alpine humus soils can be clearly separated upwards from Alpine iron-humus. podzols.

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The writer studied the yellowish orange colored soil developed on the granitic rocks of Oshima Island, Yamaguchi Prefecture. The locality belongs to the "Setouchi" climatic region, and more widely to the warm-temperate forest zone. Geologically it is situated in the "Ryoke" metamorphic zone (granodiorite). Primary minerals in sand fractions (coarse and fine sands) consist predominantly of acidic to neutral plagioclase, biotite and quartz. Except for the upper horizons, soil color is yellowish orange. This soil is, however, mainly at the stage of physical disintegration, accompanied by weak chemical decomposition (siallitization). Analytical data show that both the humus accumulation and clay formation are not so intensive and the soil is still at the younger stage of development. These characteristics of weathering and soil formation seem to reflect considerably the lithological nature of parent rock (granodiorite). Chemical properties of this soil are characterized by low values of pH, exchangeble acidity, C.E.C., and exchangable Ca and Mg, while the degree of base saturation are somewhat high. Leaching of base is fairly distinct through the profile. The contents of free oxides (Fe, Al) are relatively high, as compared with those of free silica. Since SiO_2/R_2O_3 mol-ratio in clay fraction (<2μ) is rather lower in surface horizon than in subsoil, slight enrichment of sesquioxides may have taken place in surface horizon. Clay minerals in this soil are mainly Al-vermiculite and metahalloysite with some amounts of mixed layer minerals and micaceous minerals. Absence of gibbsite in this soil is notable. The nature of weathering and soil formation of this soil is thought to be initial stage of siallitization. Judging from the properties above-mentioned, this soil corresponds neither to Brown forest soils and their affinities distributed in north-east Japan, nor to Red-Yellow soils developed on Pleistocene terraces and hills in south-west Japan. Instead, another taxonomical name should be devised to this soil at the level of genetic soil type.

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