Smithsonian paleontologist Bill DiMichele and colleagues Howard Falcon-Lang (University of Bristol), John Nelson and Scott Elrick (Illinois State Geological Survey), and Phil Ames (Peabody Coal Company) discovered the remains of one of the world's oldest tropical rainforests, preserved in the ceiling of a coal mine 250 feet below the surface.
The rainforest extends over more than four square miles as the roof of two adjacent underground coal mines in eastern Illinois. This may be the largest single-time-period fossil forest found in the fossil record.
Here is Neuropteris ovata, part of a frond of a “seed fern”, seen on the mine ceiling or roof. The roof is the forest floor of the swampy environment in which these plants were living. Miners removed the coal bed exposing the forest floor – this would be the “worm’s eye view” (if worms had eyes!). Seed ferns were seed-bearing plants that had large, highly compound leaves much like ferns (hence their descriptive name).
For more information, check out Four Square Miles of Carboniferous Forest Discovered, a Natural History Highlight.