  I have been too conservative in `A review of the properties of the scattered
starlight which contaminates the spectrum of reddened stars' (NewA, 2002, 7/4,
191) concerning the conditions implied by an additional component of scattered
light in the spectrum of reddened stars. I will review and simplify these
conditions. Implications for the column density of the scatterers will then be
discussed. Estimates for coherent Rayleigh scattering by hydrogen are in
excellent agreement with the observations.
