  We point out two extensions of the relation between matrix models,
topological strings and N=1 supersymmetric gauge theories. First, we note that
by considering double scaling limits of unitary matrix models one can obtain
large N duals of the local Calabi-Yau geometries that engineer N=2 gauge
theories. In particular, a double scaling limit of the Gross-Witten
one-plaquette lattice model gives the SU(2) Seiberg-Witten solution, including
its induced gravitational corrections. Secondly, we point out that the
effective superpotential terms for N=1 ADE quiver gauge theories is similarly
computed by large multi-matrix models, that have been considered in the context
of ADE minimal models on random surfaces. The associated spectral curves are
multiple branched covers obtained as Virasoro and W-constraints of the
partition function.
