  We present the results of self-consistent calculations of the electronic
shell and supershell structure for clusters having up to 6000 valence
electrons. The ionic background is described in terms of a homogeneous jellium.
The calculations were performed for a series of different electron densities,
resembling Cs, Rb, K, Na, Li, Au, Cu, Tl, In, Ga, and Al, respectively. By
analyzing the occupation of the energy levels at the Fermi energy as a function
of cluster size, we show how the shell and supershell structure for a given
density arises from the specific arrangement of energy levels. We investigate
the electronic shells and supershells obtained for different electron
densities. Using a scaling argument, we find a surprisingly simple dependence
of the position of the supernodes on the electron density.
