Abstract
Chiasma frequencies in male and female meiocytes in Tulbaghia follow the general rule and are higher in the female. A feature of female meiosis is a shift in the proximal localization, found in the male meiocyte, toward a more median and distal distribution of chiasmata. The results in Tulbaghia, together with the findings of other authors in many other organisms, indicate that there are two systems of recombination operating in any one species. The two systems tend in effect to stabilize favourable gene combinations and to facilitate their establishment in outbred species.