British Roses and Hybridity

Abstract

THE genus Rosa, along with the brambles (Rubus); hawkweeds (Hieracium), and certain other polymorphic genera, has long furnished serious problems to the systematic botanist. Darwin spoke of the kind of variability which these genera show as “independent of the conditions of life,” meaning that the differences exhibited are “of no service or disservice to the species,” and are therefore not directly subject to natural selection. Modern geneticists would largely agree with that point of view.