  If the dual Meissner effect due to abelian monopole condensation is the quark
confinement mechanism of QCD as suggested in recent Monte-Carlo simulations of
lattice QCD, new axial-vector and scalar bosons with the mass of O(1GeV) would
appear as physical states which are different from ordinary hadrons and
glueballs. The axial-vector boson can not decay into ordinary color-singlet
hadrons and glueballs owing to a remainig global discrete permutation symmetry
with respect to colors (Weyl symmetry) if the vacuum respects the symmetry as
suggested from lattice MC simulations.
