of a single galaxy as a function of the mass of the hosting halo/subhalo, together with the corresponding mass-to-light ratio. Shown are curves for both K- and $b_J$ bands. We caution that the results for the latter band should be treated with some reserve. This counting method is not entirely adequate to get the mass-luminosity relation in the blue, due to complications arising from recent star formation, although it is still interesting to compare the differences obtained from using two different luminosity functions.

Destroyed subhaloes and the subhalo mass fraction {#sect:destroyedsh}
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As mentioned, a potentially important correction to the non-parametric model in paper I is to account for subhaloes which have been completely destroyed. The study of this evolution of the subhalos and their eventual destruction, with the subsequent merger (or not) of their galaxy with the central one, is a very interesting topic by itself, which is still not completely understood but which is essential to a complete understanding of the formation of BCGs. However, such a detailed look at this question is beyond the scope of the present paper; here, we are merely interested in a simple model to account for how much mass was in these 