  An "expanded" description is introduced to examine the spinor-monopole
identification proposed by Strassler for four-dimensional $\cal N$ = 1
supersymmetric Spin(10) gauge theories with matter in F vector and N spinor
representations. It is shown that a Z_2 monopole in the "expanded" theory is
associated with massive spinors of the Spin(10) theory. For N=2, two spinor
case, we confirm this identification by matching the transformation properties
of the two theories under SU(2) flavor symmetry. However, for N $\ge$ 3, the
transformation properties are not matched between the spinors and the monopole.
This disagreement might be due to the fact that the SU(N) flavor symmetry of
the Spin(10) theory is partially realized as an SU(2) symmetry in the
"expanded" theory.
