  I classify exotic hadrons into two types, "genuine" and "hidden" exotics, and
propose that the "hidden" exotics would be interpreted as "chiralons" in the
~U(12)_SF times O(3,1)_L-classification scheme of hadrons. Based upon this
conjecture I investigate the mass spectrum of 1S, 1P, and 2S states for the
ccbar system by use of a phenomenological mass formula with the spin-dependent
interactions and present possible assignments for exotic neutral
charmonium-like states which were recently discovered. It is also mentioned
that some J^PC-exotic states predicted in this scheme might correspond to those
found in a recent lattice QCD calculation of the charmonium spectrum.
