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Article: Polypodiophyta
- Article from:
- The Columbia Encyclopedia, Sixth Edition
CopyrightThe Columbia Encyclopedia, Sixth Edition. Copyright 2008 Columbia University Press. (Hide copyright information)
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Polypodiophyta , division of the plant kingdom consisting of the plants commonly called
ferns
. The ferns are vascular plants with stems, roots, and leaves. The small and inconspicuous
gametophyte
and the large spore-producing fern plant are quite independent of each other. The sporophyte plant, which is the plant form popularly recognized as a fern, may have an erect stem of more than 50 ft (16 m) in height, or a prostrate stem lying in or on the ground. The anatomy of fern stems, especially in the arrangement of the vascular bundles, differs greatly from group to group and is used as a means of interpreting the evolutionary relationships of the various groups. Typically, the leaf, or ...