  We calculate the chiral anomaly in the neighbourhood of the fixed point space
M_h which is constructed by the group action of a discrete symmetry h on a
compact manifold M. The Feynman diagrams approach for the corresponding
supersymmetric quantum mechanical system with twisted boundary conditions is
used. The result we derive in this way agrees with the generalization of the
ordinary index theorem (the G-index theorem) on the spin complex.
