[en] A physically meaningful macroscopic description of the spectrum of neutrons emitted in nuclear fission has been derived and the well known result has been compared with accurate data on ²⁵²Cf. A second example, derivation of an expression for resonance-averaged cross sections can be calculated. If constrained only by the range of the spectrum of compound nuclear levels it produces the Gaussian Orthogonal Ensemble (GOE) of Hamiltonian matrices that again yields expressions for average cross sections. Both avenues give practically the same numbers in spite of the quite different cross section formulae. These results have been employed in a new model-aided evaluation of the ²³⁸U neutron cross sections in the unresolved resonance region. 1 tab., 6 figs., 44 refs