  We present a solution to the apparent discrepancy between the radial gradient
in the diffuse Galactic gamma-ray emissivity and the distribution of supernova
remnants, believed to be the sources of cosmic rays. Recent determinations of
the pulsar distribution have made the discrepancy even more apparent. The
problem is shown to be plausibly solved by a variation in the CO-to-N(H2)
scaling factor. If this factor increases by a factor of 5-10 from the inner to
the outer Galaxy, as expected from the Galactic metallicity gradient, we show
that the source distribution required to match the radial gradient of gamma-ray
can be reconciled with the distribution of supernova remnants as traced by
current studies of pulsars. The resulting model fits the EGRET gamma-ray
profiles extremely well in longitude, and reproduces the mid-latitude inner
Galaxy intensities better than previous models.
