Pteridophytes are a phylum of plants They are the vascular plants those having xylem and phloem tissues that reproduce by releasing spores rather than seeds and they include the highly diverse true ferns and other graceful primarily forest-dwelling plants There are about eleven thousand different species of Pteridophytes making them the most diverse land plants after the flowering plants angiosperms Pteridophytes may represent the closest living relatives sister group to the seed plants As in seed plants the greatest diversity of Pteridophytes is found in the tropics with only about six hundred species adapted for life in temperature climates This book is a compilation work and embodies a fairly comprehensive treatment of the fundamental facts and aspects of Pteridophyta