  Several general results are derived for diffuse waves in anisotropic solids,
including concise expressions for the modal density per unit volume and for the
participation factor matrix G. The latter is a second order tensor which
describes the orientational distribution of diffuse wave or reverberant energy,
and reduces to the identity I under isotropy. Calculations of G for a variety
of example materials show significant deviation from I even under moderate
levels of anisotropy.
