EN--FernWith the common name fern is commonly known that all plants belong to Pteridophyta (Pteridofyta). The best known of these is the aquiline Pteridion (Pteridium aquilinum), common native to Greece, the only race of its kind Pteridion (Pteridium) family Ypolepidides (Hypolepidaceae). This family formerly constituted, together with other families, a single family, named Polypodiides (Polypodiaceae). The spread varies from coastal to mountainous areas. Used mainly for its leaves (for creating shoddy housing and packaging of fruits), while in the past has been used to extract potash, because it has high potassium content. With the common name is known fern and many other types Pteridikon, grown as an ornamental.DescriptionThe fern has genuine roots, stems and leaves, but not forming flowers and, of course, not nuts and seeds, so it is classified as cryptogam plant. The multiplication is done with spores, which are formed in sporangia on the rear surface of the leaflets compound leaf. The spores are dispersed by wind and germinate if found in ideal conditions of humidity and temperature. However, it is possible to multiply and pieces of rhizomes. The height of ferns (in the aquiline type pteridion) reaches 2 meters. The very large leaves are usually tripteroeidi and complex, with long stems, hairy at the base. Leaf divided into parts, called pteridia. There, at the bottom of pteridion, is the formation of sporangia in piles. These are covered by membranous sheath and returned curbs.