Morphological peculiarities, as defined from isophote asymmetries and number of detected shells, jets or similar features, have been estimated in a sample of 117 E classified galaxies, and qualified by an ad hoc S_2_ index. Objects with S_2_<1 are "normal" (Nop subsample), the other are "peculiar" (Pec subsample). The two subsamples are intercompared as regards the Fundamental Plane, Faber-Jackson relation, dust content from IRAS fluxes, occurence of Kinematically Distinct Cores and stellar populations. The Nop subsample objects displays tight correlations between central velocity dispersion (or mass) and the population indices U-B, B-V, B-R, V-I, Mg_2_, Hbeta, <Fe>, Mg_b_. Part of the Pec objects deviate from these correlations, with blue "residuals" indicating a Younger Population mixed with the old one. This does not occur for other Pec objects. This subsample is thus classified in two families: i.e. the 'YP', or NGC 2865 family, and the 'NP' or NGC 3923 one. This distinction is quantified by a Mean Index of a Younger Population, or 'MIYP' with near zero values for the 'NP' objects and relatively large negative values for the 'YP'.