New specimens of Phasmatocycas and Taeniopteris from the original Lower Permian locality in Kansas demonstrate organic attachment of the two and corroborate Mamay's hypothesis that Phasmatocycas and Taeniopteris were parts of the same plant. These forms also suggest that cycads evolved from taxa with entire leaves; i.e. Taeniopteris, rather than from pteridosperms with compound leaves. ?? 1986.
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Taeniopterid lamina on Phasmatocycas megasporophylls (Cycadales) from the Lower Permian of Kansas, U.S.A.