The hyperoctahedral group acting on R-N is the Weyl group of type B and is
associated with a two-parameter family of differential-difference operators
{T-i: 1 less than or equal to i less than or equal to N}. These operators
are analogous to partial derivative operators. This paper finds all the pol
ynomials h on R-N which are harmonic, Delta(B)h = 0 and annihilated by T-i
for i > 2, where the Laplacian Delta(B) = Sigma(i=1)(N) T-i(2). They are gi
ven explicitly in terms of a novel basis of polynomials, defined by generat
ing functions. The harmonic polynomials can be used to find wavefunctions f
or the quantum many-body spin Calogero model.