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The N-S drift of sunspot groups has been studied in a different way than previously, using positions of recurrent groups of the years 1874-1976. The existence of the meridional motions, the general shape of the drift curves, and the dissimilarity between these curves around sunspot maxima and minima, are all confirmed. In addition, also for the angular velocity of the Sun the same material gives differences around the times of sunspot maxima and minima.

The question is studied whether the one-year solar oscillation found by V. F. Chistyakov for the years 1965-1973 can be traced in the observations of sunspots of 1874-1971 published by Greenwich Observatory. The result is negative. But the study leads to the following two conclusions: (1) The average observable centres of gravity of spot groups are variably displaced towards the central meridian or towards the limb, the time scale of this variability being of the order of 70 years. Thus the angular velocity should be determined from recurrent groups in transit of the central meridian only.(2) The angular velocity will be smaller when determined from older spots.

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