BRANCHING IN PACHYCAUL SENECIOS: THE DURIAN THEORY AND THE EVOLUTION OF ANGIOSPERMOUS TREES AND HERBS

Authors


Summary

The giant groundsels (Senecio L. subg. Dendrosenecio [Haum. ex]Hedb.) are tropical branching pachycaul trees in a predominantly temperate herbaceous group. Other pachycaul Senecio spp. of Africa with dendrosenecio-branching are related to tropical herbs, shrubs and lianes; the pachycaul cabbage-trees of St Helena include the he-cabbage tree with dendrosenecio-branching. It is postulated that the pachycaul tree with dendrosenecio-branching is the primitive condition for at least some alliances in the Senecioneae. The hypothesis is tested by reviewing the taxonomic distribution of the pachycaul trees with such branching in Senecioneae throughout the world and its usefulness by a consideration of the origin of herbs and trees in the Compositae.

Ancillary

Advertisement