  In a recent paper, we considered the effects of the torus lattice topology on
the two-point connectivity of $Q-$ Potts clusters. These effects are universal
and probe non-trivial structure constants of the theory. We complete here this
work by considering the torus corrections to the three- and four-point
connectivities. These corrections, which depend on the scale invariant ratios
of the triangle and quadrilateral formed by the three and four given points,
test other non-trivial structure constants. We also present results of Monte
Carlo simulations in good agreement with our predictions.
