The Pteridophytes include horsetails and ferns. Pteridophytes are used for medicinal purposes and as soil-binders. They are also frequently grown as ornamentals. Evolutionarily, they are the first terrestrial plants topossess vascular tissues – xylem and phloem.The pteridophytes are found in cool, damp, shady places though some may flourish well in sandy-soil conditions.

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Feature	Description
General Characteristics of Pteridophyta
Common Name	Pteridophytes
Groups Included	Horsetails and ferns
Uses	Medicinal purposes, soil-binders, ornamental plants
Evolutionary Significance	First terrestrial plants to possess vascular tissues (xylem and phloem)
Habitat	Cool, damp, shady places; some in sandy-soil conditions
Dominant Phase	Sporophyte (differentiated into true root, stem, and leaves)
Leaves	Small (microphylls) as in Selaginella or large (macrophylls) as in ferns
Sporophylls	Leaf-like appendages that bear sporangia; can form strobili or cones (Selaginella, Equisetum)
Spores	Produced by meiosis in spore mother cells; germinate to form gametophytes
Gametophyte	Inconspicuous, small, multicellular, free-living, mostly photosynthetic thalloid (prothallus); require cool, damp, shady places
Gametophyte Organs	Antheridia (male), archegonia (female)
Water Requirement	Needed for fertilization; male gametes (antherozoids) transfer to archegonium
Fertilization	Fusion of male gamete with egg in archegonium forms zygote; zygote develops into sporophyte
Spore Types	Homosporous (similar spores), Heterosporous (macro and micro spores)
Heterospory	Selaginella and Salvinia produce two types of spores: macrospores (female gametophytes) and microspores (male gametophytes)
Zygote Development	The female gametophytes in these plants are retained on the parent sporophytes for variable periods. The development of the zygotes into young embryos takes place within the female gametophytes. This event is a precursor to the seed habit considered an important step in evolution.
Life Cycle	The diploid sporophyte is represented by a dominant, independent, photosynthetic, vascular plant body. It alternates with multicellular, saprophytic/autotrophic, independent but short-lived haploid gametophyte. Such a pattern is known as haplo-diplontic life cycle. All pteridophytes exhibit this pattern.
Classification	Psilopsida – Psilotum Lycopsida – Selaginella, Lycopodium Sphenopsida – Equisetum Pteropsida – Dryopteris, Pteris, Adiantum