Calcareous nannoplankton thanatocoenoses have been investigated in 437 surface sediments collected from seas around the Japanese Islands and 34 species are identified. The geographical distributions of coccolith species are delineated separately from coastal (Gephyrocapsa oceanica, Helicosphaera carteri s.l. and Braarudosphaera bigelowii) to oceanic water forms (Florisphaera profunda, Calcidiscus leptoporus, and Rhabdosphaera clavigera) and from cold (Coccolithus pelagicus) to warm water forms (F. profunda, R. clavigera, Umbilicosphaera sibogae and Calciosolenia spp.), as determined by oceanic conditions. The Q-mode cluster analysis of the coccolith floras yields ten biotopes based on the distribution pattern of characteristic species. These biotopes can be explained by the combination of salinity and temperature. Transfer functions formulated through multiple regression analysis relating the assemblages to such parameters as mean annual surface temperatures and salinities also give accurate estimates for water temperature and salinity, with standard errors of 1.30℃ and 0.14‰, respectively. Temperature and salinity, therefore, are important parameters in controlling the distribution of coccolith floras in this area. Transfer functions have been applied to coccolith floras, which have existed for the last 22, 000 years and preserved in sediments penetrated by three piston cores in the present-day domain of the Kuroshio Current and of the Kuroshio front. The warm and cool events contemporary to the well known series of episodes in the Atlantic Ocean, and the phase called the Yayoi regression at about 2, 000 years B.P. are recognized
