1. From the mineralogical composition of the sand fractions, it is considred that the weathering products of limestone intercalating the thin layers of biotite schist were covered by dacitic volcanic ash, and further these materials were mixed by transportation. After then the mixed materials were covered by andestic volcanic ash.
2. It was confirmed that montmorillonite, hydrated halloysite, illite, gibbsite and kaolinite occur in the soil profile.
3. The weathering sequence of the parent materials seems to be as follows.
Volcanic ash influenced by the weathering of limestone→hydrated halloysite→montmorillorite (+gibbsite)

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A cursory survey on subsolidus equilibria in the system NaAlSiO₄-KAlSiO₄ was made through sintering of mixtures of chemicals in the proper proportions. The phases were identified by means of the X-ray diffractometer. The results ane shown in Figs. 1 and 2, and Tables 1 and 2.
There exists a large miscibility gap between the fields of nepheline and kalsilite. Potassium-rich nepheline stablle at high temperatures should unmix under equilibrium conditions at lower temperatures, giving kalsilite together with more sodic nepheline, as shown in Fig. 3.
An unidentified phase “A” is formed at lower temperatures than the orthorhombic form in the region with higher K/Na ratios than kalsilite.
The unit cell dimensions of kalsilites were measured as shown in Table 2.

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We found very close relations between crystal structure and morphology in pyrites. This is shown in Fig. 1, sulfur atoms are projected on (001) plane, and it can br shown in this picture that crystal planes e (210), é (210), a (100), b (010) and striation faces are parallel to each sheet structures of sulfur atoms. The sheet planes of a (100) and b (010) are not equivalent in this projection, so that in actual crystal planes there is striated on a (100) face, and is not striated but lineated on b (010) face, so far as in this section, because b (010) face striated parallel to zone [100]. It is expected that density of sulfur sheet structures are, in general, proportional to the face reflectivity than area of crystal faces.
For these reason, we classified about crystal growth of pyrites in next three stage.
(1) growth of a (100) face.
(2) growth of e (210) face.
(3) growth of o (111) and other faces.
These assumption shows a good agreement with data in recent papers on crystal habit of pyrites by Mr. I. Sunagawa.

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The limonite ores from the Horaitakamatsu Mine may be classified into three types according to their external appearance and mineral compositions as follows:
(1) Dark brown compact ores, composed of goethite only.
(2) Light reddish clayey ores, characterized by the presence of hematite and the intricated mineral contents, namely, montmorillonite, α-cristobalite, quartz, tridymite, goethite and hematite.
This complication is ascribed to the fact that the clay altered from volcanic ash mingles in this ores.
(3) Dark yellow clayey ores, composed of goethite and quartz.
A limonitic substance replacing a kind of moss is found in this mine, and from the results of its investigations, it is ascertained that it is not hydrous ferric oxide but basic ferric sulphate. The results were reported in another paper.

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There is a distinct difference in the distribution of the igneous rocks between the western and the eastern part of the Hidaka metamorphic zone. The peridotites and gabbroic rocks are widely distributed in the western part. The granites mainly occur in the eastern part.
Meguro district is situated in the south-eastern part of the Hidaka Mountains. From petrological features, metamorphic zone of this district can be classified into the following six zones. 1. hornfels, 2. schistose hornfels, 3. banded gneiss, 4. cordierite migmatite, 5. gneissose migmatite, 6. granitic migmatite. These metamorphic rocks and migmatites are intruded by dikes of basic igneous rocks, such as diabase, dioritic gabbro, hornblende gabbro and amphibolite. It seems probable that the above-mentioned basic plutonic complexes and the basic dikes are geneticaly related. The diabases which occur as minor dikes (2-3m in average width) are more abundant than the other dike rocks.
The diabase may furnish clues that will suggest further data necessary to solve a problem of the mutural relation between the migmatites and the basic igneous complexes. In the present paper, the writer have described the mode of occurrences and the microscopical features on the diabases. Some considerations on the distribution, alteration and intrusion of the diabases are given.

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