  The quantization of the superclassical system used in the proof of the index
theorem results in a factor of $\hbar^{2}R/8 $ in the Hamiltonian. The path
integral expression of the kernel is analyzed up to and including 2-loop order.
The existence of the scalar curvature term is confirmed by comparing the linear
term in the heat kernel expansion with the 2-loop order terms in the loop
expansion.
