A Systematics and Phenomenology of Meson Family

Previous studies on a systematics and phenomenology o~ meson family are reviewed and extended based on the intuitive pictures. In these discussions, the triplet configurations of hadrons are extensively used, from which the meaning of the selection principle is made clear. This principle is applied to the meson-baryon vertices. We further suggest an indirect test of both the ur-baryon mcdels and the non-relativistic descriptions of meson nonets, where the E1-transitions, 1+-g~1--~+7, are taken as the test processes.