A simple protostele, exarch-polyarch in one species (S.
The stem had a single stele, the primary xylem of which was polyarch and centripetally developed.
The axis of the cone in Cheirostrobus contains a polyarch stele, with solid wood, from the angles of which vascular bundles pass out, dividing in the cortex, to supply the various segments of the sporophylls.
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