Experimental observations of ππ* states of even symmetry in aromatic hydrocarbons from two-photon and transient absorption studies are reviewed. In both cases the use of polarized light allows band assignment. Regularities are seen in the dependence of band energies on the number of aromatic rings. The experimental data are qualitatively discussed on the basis of the simple perimeter model for aromatic hydrocarbons. Limits of the treatment are pointed out.