Evidence for introduced taro (Colocasia esculenta) and lesser yam (Dioscorea esculenta) in Lapita-era (c. 3050–2500 cal. yr BP) deposits from Bourewa,southwest Viti Levu Island,Fiji

Starch residue, pollen and phytolith analysis was carried out on coralline deposits from a c. 3050–2500 cal. yr BP Lapita site at Bourewa, Viti Levu, Fiji. Starch grains, calcium oxalate crystals and xylem cells of introduced Colocasia esculenta and Dioscorea esculenta were identified, involving a process of elimination of possible taxa by cross-correlation of microfossil types. The data provide an eastward extension of direct evidence of Lapita horticulture in Remote Oceania previously identified in Vanuatu.     

Meteor radar observation at Kyoto in two C.T.O.P. periods (July 20–August 7, 1978, and March 13–29, 1979)

Meteor radar data taken in 1978–1979 at Kyoto station (35°N, 136°E) are processed statistically by Groves' algorithm (1959). Analysis is done especially for data in two C.T.O.P. campaigns carried out in summer and in spring to study a seasonal variation of tides. The reliability of the algorithm is clarified by a simulation with a realistic model. Vertical wavelengths of the diurnal tide and the semidiurnal tide are estimated from height profiles. The diurnal tide becomes evanescent in summer, and the semidiurnal tide appears to be the S_2,2 mode in summer and the S_2,4 mode in spring. This suggestion regarding the semidiurnal tidal modes agrees with the latitudinal variation deduced from many other meteor radar data. Tidal wave energy in the meteor region is estimated. A sudden enhancement of energy is observed in both the diurnal and the semidiurnal tides. There is a clear correlation between an energy decrease of the diurnal tide and an energy increase of the semidiurnal tide.