Flowering Plant Gateway Various paths for exploration or comparison of four major flowering plant classification systems (Cronquist, Takhtajan, Thorne and the Angiosperm Phylogeny Group system). From Texas A&M University. http://www.csdl.tamu.edu/FLORA/newgate/cronang.htm

OSU Seed Biology Program - SeedID Index Photographs of the seeds of selected plants. http://www.ag.ohio-state.edu/~seedbio/seed_id/index.html

The Families of Flowering Plants A taxonomical database with descriptions and illustrations of each family. http://www.biodiversity.uno.edu/delta/angio/

Angiosperm Phylogeny Phylogenetic trees, technical descriptions of all orders and families, references, and links. By Peter Stevens of the Missouri Botanical Garden. http://www.mobot.org/MOBOT/Research/APweb/

Angiosperm Images Extensive collection, organized by family. http://www.albion.edu/plants/ANGIFAMS.HTM

Marattia douglasii image http://www.botany.hawaii.edu/faculty/carr/images/mar_dou.jpg