231-234A study is made of noon foF2over a period of one solar cycle (1958-69) at some pairs of magnetically near-conjugate places in the eastern and central zones with dips (I) 0-60°, Seasonal dependence of the sensitivity of foF2 on solar activity is studied and the differences in the seasonal variation of foF2 are shown for low and high solar activity epochs, It is found that the seasonal variation of noon foF2 at dip-conjugates are significantly different, and the change-over seems to occur at the geographic equator, The midlatitude winter anomaly of foF2 found in north is not observed at the southern dip-conjugate till near the peak of the sunspot cycle, The results are discussed specially with reference to the neutral wind and the associated changes in the gas composition
