For the serious amateur paleobotonist, there are two more sites that have lots of links to persue: Boggy’s links and Links for Paleobotonists. The latter has a plethora of sites with ancient plant reconstructions.
It’s hard to find places that evoke the time before plants. I remember getting that primordial feeling just once on an island in the Great Salt Lake. It was sunset, and I was looking west towards the sea of brine and distant salt flats. Not a plant in sight. The greening of the land was an interesting time. An article entitled Lush Life by Marylyn Davis in the Southern Illinois University Carbondale’s Perspective, reports on recent progress in reconstructing the early plant lineages. Sorting out the early relationships from fossils has not been easy, but genetic information promises to clear things up. Go to The Conquest of the Land, a site at the University of the West Indies in Barbados, for a quick overview of the ties land plants have to aquatic green algae (they share starch as a food reserve, cell walls made of cellulose microfibrils, and the same photosynthetic pigments) and to learn about the difficulties the first colonizers of dry land had to overcome, such as desiccation, lack of support, and the need for a way to disperse spores through the air.
As for Darwin’s “abominable mystery,” the sudden appearance of the first flowering plants in the fossil record, more new finds will undoubtedly help. Currently the oldest flowering plants are found in China. See the National Geographic article “Dino-Era Fossil—The First Flower?,” which dates the rise of the first angiosperms to 124 million years ago. (Angiosperms became the dominant plants of today and include all our important food crops.) A more recent news brief in the People’s Daily Online makes a claim of 145 million years. Whatever, the date, the prize for most primitive “living fossil” of the flowering plants goes to Amborella trichopoda, a small shrub that, in the United States, can be found only in the arboretum at the University of California in Santa Cruz. See “Rare specimens at the Arboretum declared most primitive living flowering plants,” an article in the university’s magazine, Currents. Amborella has tiny greenish-yellow flowers and red fruit, and grows wild only on the South Pacific Island of New Caledonia. No doubt Darwin would have wanted one in his green house.