  We consider the polarization arising from scattering in an envelope
illuminated by a central anisotropic source. Spherical harmonics are used to
describe both the light source anisotropy and the envelope density distribution
functions of the scattering particles. This framework demonstrates how the net
resultant polarization arises from a superposition of three basic "shape"
functions: the distribution of source illumination, the distribution of
envelope scatterers, and the phase function for dipole scattering. Specific
expressions for the Stokes parameters and scattered flux are derived for the
case of an ellipsoidal light source inside an ellipsoidal envelope, with
principal axes that are generally not aligned. Two illustrative examples are
considered: (a) axisymmetric mass loss from a rapidly rotating star, such as
may apply to some Luminous Blue Variables, and (b) a Roche-lobe filling star in
a binary system with a circumstellar envelope. As a general conclusion, the
combination of source anisotropy with distorted scattering envelopes leads to
more complex polarimetric behavior such that the source characteristics should
be carefully considered when interpreting polarimetric data.
