British Ferns
- The Delta database provides botanical descriptions of all species found in the British Isles.
- http://delta-intkey.com/britfe/

Plant Diversity: Ferns in The Wet Tropics
- Information and photographs of several ferns that grow in northern Australia.
- http://www.wettropics.gov.au/pa/pa_ferns.html

Ferns et al of New England and Bermuda
- Lists all native pteridophyte species and some hybrids, with photographs of most and data pages for some.
- http://www.nefern.info/

Fern Siam
- Images, taxonomic information, online forum, and other resources about ferns in Thailand. Mostly in Thai language, with some English.
- http://www.fernsiam.com/

Phylogeny and evolution of ferns (Monilophytes)
- Scientific paper from American Journal of Botany 2004 showing that Psilotophyta and Equisetophya are in the Monilophyte clade with the other ferns.
- http://www.pryerlab.net/publication/fichier494.pdf

Gallery of Connecticut Ferns
- Photos and brief information indexed by common and scientific names.
- http://www.ct-botanical-society.org/ferns/

Ferns of Barbados
- Checklist plus distribution data and links for each species.
- http://scitec.uwichill.edu.bb/bcs/staff/lec/ferns.htm

American Fern Society
- Information on the biology and cultivation of ferns; activities of the society including a spore exchange and publication of Fiddlehead Forum, American Fern Journal, and Pteridologia.
- http://amerfernsoc.org/

Ferns of the Canberra Region
- A site about ferns in southeastern Australia, their ecology, how to grow them, information on ferns in general, with numerous photographs.
- http://www.home.aone.net.au/byzantium/ferns/

Ferns of Fern Forest and South Florida
- Photographs and descriptions of the ferns of southern Florida.
- http://fig.cox.miami.edu/~scofield/sofl_plants/fern_index.html

Ferns of Great Britain and Ireland
- Small images of 39 antique prints by Thomas Moore, 1855.
- http://rare-prints.com/ferns_main.htm

British Fern Species
- Searchable database.
- http://midwales.com/westhill/mydbfern/

Pterophyta Taxa
- List of all families and genera, with numbers of species and ranges.
- http://www.science.siu.edu/landplants/Pterophyta/pterophyta.taxa.html

Phylum Pterophyta
- Includes a description of the fern life cycle, list of families and genera, and links to images of selected representatives.
- http://www.science.siu.edu/landplants/Pterophyta/pterophyta.html

Pterophyta
- Introduction to the systematics of the ferns, with family descriptions and images.
- http://botit.botany.wisc.edu/courses/systematics/Phyla/Pterophyta/Pterophyta.html

Leptosporangiate Ferns
- Next to the flowering plants, the leptosporangiate ferns are the most diverse group of living land plants. Estimates place their diversity at about 12,000 species in around 300 genera. This page is part of the tree of life phylogeny project.
- http://tolweb.org/tree?group=Leptosporangiate_Ferns&contgroup=Filicopsida

Filicopsida
- Introduction to ferns from the Tree of Life project.
- http://tolweb.org/tree?group=Filicopsida&contgroup=Embryophytes

Introduction to the Ferns
- The ferns are an ancient lineage of plants, dating back to at least the Devonian. They include three living groups - Marattiales, Ophioglossales, and leptosporangiate ferns - as well as a couple of extinct groups.
- http://www.ucmp.berkeley.edu/plants/pterophyta/pteridopsida.html