  We present de Vaucouleurs' effective radii in B and R bands for a sample of
Molonglo Reference Catalogue radio galaxies and a control sample of normal
galaxies. We use the ratio of the scale lengths in the two bands as an
indicator to show that the radio galaxies tend to have excess of blue color in
their inner region much more frequently than the control galaxies. We show that
the scale length ratio is a useful indicator of radial color variation even
when the conventional color gradient is too noisy to serve the purpose.
