Pollen Germination in Relation to Group Size

In recent experiments involving the germination of the pollen grains of Vinca rosea, it was observed that relatively poor germination occurred in isolated grains and among those grains aggregated in small groups (Beams and King, 1944). These preliminary observations seemed to warrant a further study of this problem. Accordingly, experiments were designed to determine some of the effects of population density on the percentage germination of these cells