  The distribution of the radial trends of the mass-to-light ratios (M/L)
within an assorted sample of early-type galaxies is discussed. Three classes of
galaxies are identified according to their M/L gradients. Two such classes are
characterized by the presence or by the absence of a radial gradient of the
dark-matter (DM) distribution. A third class contains objects which are likely
undergoing interaction; they exhibit steep M/L gradients which are possibly the
result of a wrong assumption on their equilibrium conditions. Finally, a
possible correlation between DM content and morphological types is briefly
discussed.
