Open directory - Pteridophyta - Plantae - Flora and Fauna - Biology

British Pteridological Society - Images and information about ferns and other pteridophytes; activities of the society including publication of the Fern Gazette, Pteridologist, and Bulletin.

Checklist of World Ferns - A compiled list of the ferns and fern allies of the world, with full botanical names, information about where they are found, and their classification.

Field Systematic Botany - Pteridophytes: an Overview - A detailed introduction to the ferns and fern allies.

Images of Pteridophyta - Part of the W3Tropicos database at the Missouri Botanical Garden.

Introduction to the Pteridophytes - An illustrated introduction to the ferns and fern allies for undergraduate students.

Natural Perspective - Ferns and Allies (Filicinophyta) - Brief introduction.

Pteridophytes: Ferns and Fern Allies - Personal site with a classification scheme, bibliography, some local checklists (Ohio and Kentucky), and an article on ferns and soil conservation.

Pteridophytes: The Ferns and their Allies - Provides information on these ferns and their allies, their structure and classification, with keys and checklists of Australian species.