Many people have attacked the problem of synthesizing the stellar population of the galaxies. We have performed such a synthesis, by using only the intensities of absorption lines in the nuclei of galaxies. It is then possible to obtain a synthesized continuous spectrum even if there are several possible solutions for the stellar composition, and the computed continuum does not vary much with the assumed model of stellar population.

The method is to fit the equivalent widths of the absorption lines using different stellar compositions. In order to avoid any instrumental effect, we have observed different lines and bands from 3500 to 8500 å in stars of various well-known stellar types and luminosity classes, under the same conditions as the galaxies.

We have applied this method to some ‘ordinary’ nuclei and to some Seyfert ones. As an example, we show the results for M81 and for NGC 1068.