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The statistical relation between solar flares of importance >2+ and the onset of geomagnetic disturbances was studied for 1949-01. Disturbances were defined as an increase in a, > 50, occurring within 13 hours or less, and these disturbances include both gradual and sudden commencement events. Associated radio noise bursts a t frequencies below 300 Mc were used to select 340 major-burst flares, and the effects of flare importance, time of solar epoch, and associated polar-capabsorption (PCA) events were considered in turn. A detailed examination was made of the effect of flare heliographic location. There is a strong positive correlation between the occurrence of major-burst flares and geomagnetic disturbances 1 to 3 days afterwards. The degree of correlation is approxi~nately doubled when the major-burst flare is associated with a PCA event. T h e most probable time delay between flares and disturbances is 1.5 to 2.0 days, and this ti~niug is relatively constant over a wide range of conditions.The dominance of northern storm-flares (Bell 1961) was confirmed for 1949-61. Detailed analysis shows that the effect is strongest for heliographic latitudes above 15" N. I n addition to this effect, there was a consistent western bias of the storm-flares in both the northern and southern hemispheres, for flares associated with either gradual or sudden commencement (SC) events, with maximum concentration occurring a t 10" W. to 15O W. Major-burst flares associated with PCA events also show this western bias; the data suggest that there is a systematic increase in east-west asymmetry in going from major-burst storm-flares to maior-burst PCA flares to PCA flares accomoanied bv mound-level cosmic-rav incieases. The corresponding longitudes of Inaximurn coicentration of the associated flares are about 10" -15" W., 45" W., and 75" W.

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