When more than two decades ago this series was planned, classi?cation at the level of higher categories was rather contentious and considered to be of little concern for this book series. Through the advancement of molecular systematics within the last decade, the outlines of a phylogenetically based family scheme of angiosperms have become ava- able. This phylogenetic scheme for the ?rst time made meaningful broader comparisons feasible and is adopted here as a guideline for the circumscription of major blocks of families. However, due to the fragility of formal higher level classi?cation...

When more than two decades ago this series was planned, classi?cation at the level of higher categories was rather contentious and considered to be of little concern for this book series. Through the advancement of molecular systematics within the last decade, the outlines of a phylogenetically based family scheme of angiosperms have become ava- able. This phylogenetic scheme for the ?rst time made meaningful broader comparisons feasible and is adopted here as a guideline for the circumscription of major blocks of families. However, due to the fragility of formal higher level classi?cation...