Presumed main axis leafy at younger stage. Lateral shoot syst ems pinnat ely branched, consisting of a penultimate branch with two lateral series of parallel ultimate branches situated in one plane. Tripinnate shoot systems may also occur. Leaves bifacial, spirally arranged, sometimes heterophyllous.
Ovuliferous cone compound; cone axis bearing spirally arranged bracts with ovuliferous dwarf-shoots arising freely in their axils. Ovuliferous dwarf-shoots bilaterally symmetrical, (slightly) flattened, provided with a number of (about 10-30) sterile scales. Fertile scales reduced in number (1- 3), more or less adaxially situated, each bearing a single inverted ovule on the abaxial surface; place of attachment ranging from sub-apical to central. Fertile and sterile scales hardly connate. Ovule/seed bilaterally symmetrical, platyspermic, seed axis bent. Nucellus free to its base; pollen chamber present; megaspore membrane cutinized.
Polliniferous cone simple, cone axis bearing spirally arranged, hyposporangiate microsporophylls. Prepollen circular to elliptical in polar view; monosaccoid.
Epidermis of leaves, bracts, scales and microsporophylls amphistomatic; stomata situated in longitudinal bands or rows. Stomatal complexes mono- to incompletely tricyclic; each with 4-9 subsidiary cells sometimes bearing papillae. Hair bases present. Papillae on ordinary epidermal cells may also occur.
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