  It is shown that the universal behavior of the spacing distribution of
nearest energy levels at the metal--insulator Anderson transition is indeed
dependent on the boundary conditions. The spectral rigidity $\Sigma^2(E)$ also
depends on the boundary conditions but this dependence vanishes at high energy
$E$. This implies that the multifractal exponent $D_2$ of the participation
ratio of wave functions in the bulk is not affected by the boundary conditions.
