Size–luminosity relation for the Sérsic components of EFIGI E and cD galaxies, and for the bulges of lenticular and spiral types with Inclination ≤ 2, all in the g band. The purple points in the 2 upper left panels represent the same relation for the E, cD and dE galaxies modeled as a single Sérsic profile. The solid line in the upper-left panel shows the linear fit of log(R_e) as a function of M_g for all EFIGI E Sérsic components, and the dashed lines are offset by ±3 times the rms dispersion in log(R_e) around the fit. These solid and dashed lines are repeated in gray in all other panels. The color of the points represents the bulge-to-total luminosity ratio in the g band, B/T_g. Both effective radii and luminosities of bulges get smaller while spanning the Hubble sequence.