[in Japanese]

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Deposits as material for the study of the Foraminifera were collected from 31 stations distributed in the shallow area of the Java Sea surrounded by Java, Sumatra and Borneo during August and September, 1933. Tests of the Foraminifera were selected by the carbon tetrachloride-method from deposits of each station.
It is found in the present work that there are three parts of sandy deposits and also of muddy ones in this region, and the Foraminifera which dwell on bottoms of seas are prolific in the former, in particular, most in the south-eastern area of Borneo, for example, deposits taken from St. 27 were composed of almost only tests of the Foraminifera (92%), while very scarce in the latter, especially remarkable in the parts of clayey deposits (less than 0.1%). The widespread species taken from most stations are Textularia agglutinans, Bigenerina nodosaria, Quinqueloculina reticulata, Cribrolinoides curta. and ect., and Reophax scorpiurus, T. foliacea, T. goësii, T. conica, Operculina complanata, Peneroplis pertusus, Amphistegina lessonii, Siderolites tetraëdra, Planorbulina larvata and Alveolinella boscii are more rbundant in sandy deposits, but the following forms in muddy ones, such as Q, lainarckiana, Q. bicostata, Spiroloculina planulata, Eponides praecinctus, Rotalia schroeteriana, and R. pulchella. In this shallow sea the Miliolidae is the most prodominant family in the qualitative and quantitative investigations, and the Textulariidae follows qualitatively, while the Rotaliidae quantitatively. Tests of pelagic forms in which species of Globigerinidac and Globorotaliidae are included, were found more frequently from deposits of stations scattered near the Strait of Sunda and the deeper area of the Java Sea due to close connections with the charaeter of the plankton. It is general that the greater an amount of sand in deposits of a station becomes, the more species of Foraminifera increase in number, but the same forms by no means occur in similar deposits in this sea.

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