Field Book: Pennsylvanian Plant Fossils of Illinois

by Charles William Collinson; Romayne Skartvedt

3. Lepidodendron. After Hirmer.

4. Sigillaria. After Hirmer.

5. Calamites. After Hirmer.

6. Sphenophyllum. After Fuller and Tippo.

7. Equisetum. The only living genus of scouring rushes. After Fuller and Tippo.

8. Megaphyton. An ancient true fern. After Hirmer.

9. Modern tropical tree fern. After Fuller and Tippo.

10. Medullosa. An ancient seed fern. After Stewart.

11. Williamsonia. An extinct cycad-like tree. After Sahni.

12. Cycas. A modern cycad. After Chamberlain.