  Solar active longitudes show a characteristic migration pattern in the
Carrington coordinate system when they can be identified at all. By following
this migration, the longitudinal activity distribution around the center of the
band can be determined. The halfwidth of the distribution is found to be
varying in Cycles 21 - 23, and in some time intervals it was as narrow as 20 -
30 degrees. It was more extended around maximum but it was also narrow when the
activity jumped to the opposite longitude. Flux emergence exhibited a
quasi-periodic variation within the active zone with a period of about 1.3
years. The path of the active longitude migration does not support the view
that it might be associated with the 11-year solar cycle. These results were
obtained for a limited time interval of a few solar cycles and, bearing in mind
uncertainties of the migration path definition, are only indicative. For the
major fraction of dataset no systematic active longitudes were found. Sporadic
migration of active longitudes was identified only for Cycles 21 - 22 in the
northern hemisphere and Cycle 23 in the southern hemisphere.
