5.4. The FG-Systems

Table IV lists six galaxies whose spectra are of a somewhat later type than those in the F group, and so they are designated FG-systems.

In this group the central concentration of light tends to contribute a larger percentage of the total luminosity. Two of the galaxies, however, NGC 5633 and NGC 6574, are small and the direct-exposure evidence does not indicate definitely whether they are, in fact, similar to the larger systems.