If f and g are two nonsingular
quadratic forms with rational integral coefficients such that f represents g integrally
over every p-adic fields and also over the reals, then it is a well-known classical result
that the genus Gen(f) of f represents g. This paper considers the question of how
many spinor genera in the genus of f will represent g, when f and g are
integral forms defined over some fixed domain of algebraic integers and when
dim(f) −dim(g) ≧ 2.