  Experimental annihilation cross sections of antineutrons and antiprotons at
very low energies are compared. Features of Coulomb focusing are observed for
$\bar p$ annihilation on protons. Direct comparisons for heavier targets are
not straightforward due to lack of overlap between targets and energies of
experimental results for $\bar p$ and $\bar n$. Nevertheless, the annihilation
cross sections for $\bar n$ on nuclei cannot be described by an optical
potential that fits well all the available data on $\bar p$ interactions with
nuclei. Comparisons made with the help of this potential reveal in the $\bar n$
data features similar to Coulomb focusing. Direct comparisons between $\bar n$
and $\bar p$ annihilations at very low energies would be possible when $\bar p$
cross sections are measured on the same targets and at the same energies as the
available cross sections for $\bar n$. Such measurements may be possible in the
foreseeable future.
