Autocorrelation analyses of K-coronameter observations made at Haleakala and Mauna Loa, Hawaii, during 1964-1967 have established average yearly rotation rates of coronal features as a function of latitude and height above the limb. At low latitudes the corona was found to rotate at the same rate as sunspots but at higher latitudes was consistently faster than the underlying photosphere. There were differences as large as 3-4 % in the rate at specific latitudes fi'om year to year and between the two hemispheres. In 1967 a nearly constant rotation was found for heights ranging from 1.125 to 2.0 R0. For 1966 there was a more complicated pattern of height dependence, with the rate generally decreasing with height at low latitudes and increasing at high latitudes.

Observations of the white light corona were made on over 900 days during the years 1964-67 at heights between 1.125 and 2.0R~ with the K-coronameter at Mount Haleakala and Mauna Loa, Hawaii. The brightness distribution of the minimurn corona was elliptical with average equatorial intensitics three times the polar. Coronal features of the new cycle at 1.125 R o occurred predominantly in the sunspot zones at 25..-30 ' latitude and in a high latitude zone which migrated toward the North pole before solar maximum. The brightness of the inner corona doubled over this period and a close association is found between the average corona and 10.7-cm solar radio flux. Electron densities in the equatorial regions were nearly twice those of Van de Hulst's model corona, in agreement with the results of recent eclipse observations.

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