Evolutionary history of plants and radially symmetrical, is an integumented megasporangium surrounded by a cupule. The megasporangium bears an unopened distal extension protruding above the multilobed integument. It is suspected that the extension was involved in anemophilous pollination. "Runcaria" sheds new light on the sequence of character acquisition leading to the seed. "Runcaria" has all of the qualities of seed plants except for a solid seed coat and a system to guide the pollen to the ovule. The first spermatophytes (literally: "seed plants") – that is, the first plants to bear true seeds – are called pteridosperms: literally, "seed ferns", so called because their
On the Movements and Habits of Climbing Plants aim. This book stands second in line to his first work on plants, "On the various contrivances by which British and foreign orchids are fertilised by insects." (1862) This work is subdivided into chapters concentrating on a particular type of climber which he divided into four main classes but Darwin, in this volume, concentrates on the two main classes, the twining plants and the leaf climbers (divided into two sub-divisions: leaf climbers and tendril bearers) The following comprise the chapters: 1. Twining plants 2. Leaf climbers 3 & 4.Tendril bearers 5. Hook and Root climbers. Inspired by reading an 1858