shown; pair members are marked by asterisks. Here and in the other figures the error bars correspond to the errors of velocity dispersion used to calculate the disk local surface density. The uncertainty of parameter $Q_c$ is not included in the error bars (according to the numerical simulations it reaches at least 20%). The same diagram as in Fig. 1a, but after the exclusion of S0-a—S0 galaxies, is shown in Fig. 1b. Though the scatter of points in these diagrams is large ($\sim 0.3~dex$), it is compatible with the errors of individual mass estimates. Therefore one can conclude that there is a general agreement between $(M/L_B)_{d}$ estimates based on marginal stability condition and those based on the stellar population evolution modeling. It is remarkable that most of the galaxies, which significantly deviate from model relation have a red color $(B-V)_0>0.7$. At least half of these galaxies are above the straight line, that is most of them have disks with significant dynamical overheating. Note, that there are both paired and isolated systems among these galaxies. Pair members occur also among the late type galaxies in Fig. 1b (11 objects), but the presented statistical data are not enough to claim their systematical 