This site was constructed by Dr. James L. Reveal, Department of Plant Biology, University of Maryland. For example, a short description of the botanical knowledge of the ancients contains links to agriculture 9000 years ago in Mesopotamia, a Assyrian herbal of the 7th century B.C., the Ebers medical papyrus with Egyptian medicinal plants from 1500 B.C., and Theophrastus. If you are considering placing course materials on the Web, this site would be a good one to peruse. Although not all of the pages are uniformly polished, there are some very nice resources at this site, notably a guide to the different classification schemes and selected plant families. This site was constructed by Dr. James L. Reveal, Department of Plant Biology, University of Maryland.
Detailed tutorials provide the background for the exercises.
A nice fossil site on the Carboniferous flora of the Mississippian and Pennsylvanian periods. This site was constructed by Monte and Harrison Hieb. The Missouri Botanical Garden has one of the most extensive collections of botanical material on the Web. The site is presented by the Missouri Botanical Garden. Central to the site is a powerful and easy to use keyword-based search engine.