  Networks generated from Voronoi tessellations of space are prototypes for
topologically disordered systems. In order to assess the effects of random
coordination on the statistical properties of energy spectra, we analyze
tight-binding models for planar topologically disordered systems. To this end,
the networks are generated by a simple topological model covering a wide range
of naturally observed random structures. We find that the energy-level-spacing
distributions exhibit level repulsion, similar to the spacings in the
energetically disordered Anderson model of localization in the metallic regime.
