  We give a description of the complete 1/N expansion of SU(N) 2D Yang Mills
theory in terms of the moduli space of holomorphic maps from non-singular
worldsheets. This is related to the Gross-Taylor coupled 1/N expansion through
a map from Brauer algebras to symmetric groups. These results point to an
equality between Euler characters of moduli spaces of holomorphic maps from
non-singular worldsheets with a target Riemann surface equipped with markings
on the one hand and Euler characters of another moduli space involving
worldsheets with double points (nodes).
