Fig. (1) (Color on line). Scanned insert from Fig. (6) of [5] showing the scatter plot of the two photon invariant mass M(γ₃γ₄) (in MeV), versus the two photon invariant mass M(γ₁γ₂) (in MeV). The areas surrounded by red squares correspond to the narrow weakly excited low mass unflavored mesons highlighted in this work. The three blue circled areas correspond to M(γγ) ≈ 743 MeV (see text). Reprinted figure with permission from Claude Amsler, Reviews of Modern Physics, Vol. 70, 1293 (1998).