seed fern

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Related to pteridosperm: seed fern

seed fern

[′sēd ‚fərn]
(paleobotany)
The common name for the extinct plants classified as Pteridospermae, characterized by naked seeds borne on large, fernlike fronds.
References in periodicals archive ?
The occurrence of downward-recurved petioles and resin rodlets in the wood strongly suggests that this tree was a medullosan pteridosperm (Zodrow 2002, 2003; Laveine and Behlis, 2007).
Architecture of the Upper Carboniferous pteridosperm frond Macroneuropteris macropkylla.
From this Psilophyton-like type were derived two lines of evolution--the lycopods, on the one hand, which retained their phylloids and dichotomous cauloids, and, on the other, all other vascular cryptogams, the pteridosperms, all gymnosperms and angiosperms.
It is probable that a considerable measure of agreement could be obtained for the thesis that ferns and' pteridosperms developed from similar Psilophyton-like ancestors with terminal fertile telomes'.
However, certain features of pteridosperm frond architecture (e.
in tree-fern or pteridosperm foliage or in calamite branching systems and foliage).
The structure of the Carboniferous pteridosperm frond Neuropteris ovata Hoffmann.
Literature on medullosalean pteridosperms, in contrast with other studied groups of Carboniferous plants, is very large and reflects a most intensively investigated Palaeozoic plant group.
This is principally consistent with, but applied with caution, that based on coal-ball observations maximal sizes of arborescent trees, pteridosperms and lycophytes alike, generally increased in the Stephanian, probably evolutionarily driven (DiMichele and Phillips 1996, p.
Charcoal and other floral remains in channel bodies are dominated by cordaitaleans, with minor pteridosperms, sphenopsids and lycopsids--the minor constituents typically confined to channel-margin situations (Falcon-Lang 1999, 2003b; Falcon-Lang and Scott 2000).