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
The Private Life of Plants idea and, you know, nodded and was very complimentary about it and said that 'Actually, I was thinking about something a little bit bolder.' And sure enough, by the end of lunch, we'd all signed up to do six hours on plants." In the same programme, Attenborough also confessed that he conceived the series partly to realise a long-cherished ambition: to visit Mount Roraima, which is featured in the last episode. Attenborough knew that the subject matter had not been covered in depth on television before, and in his autobiography, "Life on Air", told of how he hit on the