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A strong debate has continued for a number of years over the magnitude of the ratio of the buoyancy flux b to the rate of production of turbulent kinetic energy from the mean velocity sheer. This ratio has traditionally been called the flux Richardson number R f. In part I of Ivey and Imberger this definition was generalized by broadening the denominator to include all sources and sinks of mechanical turbulent kinetic energy, the net being defined as m. It was shown that for mechanically energized turbulence (m> 0, b> 0) the magnitude of R f was completely determined by the magnitude of the overturn Froude Fr T and the Reynolds Re T numbers By contrast, for the penetrative convection case (b< 0) R f was shown to be dependent only on the distance from the source of buoyancy.