  It is by now well known that the wave functions of rational solutions to the
KP hierarchy (those which can be achieved as limits of the pure n-soliton
solutions) satisfy an additional eigenvalue equation for ordinary differential
operators in the spectral parameter. This property is known as
``bispectrality'' and has proved to be both interesting and useful. In this
note, it is shown that certain (non-rational) soliton solutions of the KP
hierarchy satisfy an eigenvalue equation for a non-local operator constructed
by composing ordinary differential operators in the spectral parameter with
translation operators in the spectral parameter, and therefore have a form of
bispectrality as well. Considering the results relating ordinary bispectrality
to the self-duality of the rational Calogero-Moser particle system, it seems
likely that this new form of bispectrality should be related to the duality of
the Ruijsenaars system.
