1) Rate of decomposition of filter paper and rice straw in soils from Kyoto University Experimental Field and 'Uji' Tea Experiment Station was investigated, and found that the rate has a close relation to nitrogen and the reaction of the soils in both dry-farm and paddy field. The rate is increased greatly by addition of N while P and K have no appriciable influence. The rate in the soil from Kyoto Univ. which is neutral in reaction was much greater than that in 'Uji' soil of which reaction was strongly acid. But the neutralization with lime in case of the latter increased the rate. 2) While in the previous cases, the application of P and K had no appreciable influence on the rate of decompositis, on other soils from 'Siga' Agr. Experiment Station which received no P, and K for continuous years, the rate was increased markedly by the application of P and K respectively. From these results it is stated that the rate of decomposition of organic matter in the soils which lack N, P and K is increased by the addition of these elements, and where the reaction is acid, it is increased by the neutralization of the acid by Ca, in the same manner as the plant growth.

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A Simple flaming device which is based on Lundegardh's principle of spectroanalysis together with a small spectro-photographic apparatus, are given as well as a simple quantitative spectroanalytical method which enables the comparison of flame spectro lines by the naked eyes. By means of the method described, potassium in ashes of rice straw and strontium and lithium content in alkali Manchurian soils were determined quantitatively. The potassium determination in the straw was controlled by the chemical method. Barium, rubisium and cesium in soils of which determination is impossible with the flame spectroanalysis, the arc-spectroanalysis was employed and compared with the results obtained by the chemical analysis.

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The nitrogenous compounds in rice and wheat straw were isolated and reported as follows : [table]

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The fate of organic bases in Genge in the process of putrefaction was investigated and found : (1.) all the organic bases in Genge were decomposed except adenin; (2.) about 76 per cent of the total nitrogen was transformed into ammoniacal nitrogen by the putrefaction so that the nitrogenous contents of 'Genge' can be considered comparatively easily decomposed form.

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The distribution and stratification of the decomposed pumices in the southern part of Kanto district, namely vicinity of Tokyo, Chiba and Kanagawa Prefectures, were investigated and the results are given in the tables.

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The previous report on this subject (J. Science of Soil and Manure (Japan.) VII, 120,1933.) dealt with the results on the same subject which were obtained under laboratory conditions, in flasks and pots. In this investigation, the same procedure was carried out in the field, in a larger scale and obtained the similar results to those which were previously reported except some ferrous iron were found even in the control and ammonium sulfate section.

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