Using KPNO helium 10830 A. synoptic charts of Carrington rotations 1716 through 1739, and by assembling a time sequence representing single latitude zone, rotational properties of coronal holes for five zones of latitudes ( +_ 10 ~ _+ 20 ~ + 40 ~ and _+ 40 ~ + 60 ~ have been examined. It seems that the rotation period of coronal holes is a function of latitude, thus reflecting differential rotation of coronal holes.

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Using Stanford large-scale magnetic field synoptic charts of rotation 1676 to 1739 and by delineating LLUMR, i.e., long-lived unipolar magnetic regions of both polarities surviving at least for four solar rotations, the semi-regular nature of their photospheric magnetic field pattern and their rotational properties have been examined. The investigation demonstrates the existence of regularities in the background field patterns as shown from the regular patterns of LLUMR rows and streams. This confirms the results of Bumba and Howard concerning regularities in large-scale photospheric magnetic field patterns. LLUMR streams seem to be arranged in a wave pattern of alternating polarities. Coronal holes and associated sections of photospheric field patterns suffer differential rotation. The rotation rates of the background field patterns which are not associated with the coronal holes are different from those which are.

Regularities in the longitudinal distribution of high-flare-activity active regions during [1964][1965][1966][1967][1968][1969][1970][1971][1972][1973][1974][1975][1976][1977][1978][1979] have been examined. The Fourier spectrum for each 30~ longitude strip in northern and southern hemispheres has been obtained. It is seen that there exist two giant longitude zones in each hemisphere and solar activity remains concentrated in one of the giant zones. It also appears that the leading edge of a giant zone is more active as compared to its following edge.