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(Botany) botany (of a xylem strand) having the first-formed xylem internal to that formed later. Compare exarch1
[C20: from endo- + Greek arkhē beginning]


(ˈɛn dɑrk)

(of a primary xylem or root) developing from the periphery; having the oldest cells closest to the core.
[1895–1900; end- + -arch having a point of origin]
end′ar•chy, n.
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References in periodicals archive ?
In the cotyledonary node, the switch for the exarch typical condition of the root to the endarch (stem) condition occurs.
Vascular bundles are scattered in ground tissue with endarch xylem.
Anatomically the switch from the exarch position of the primary xylem of the radicle to the endarch position in the cotyledons takes place in the very basal part of the radicle (Rao 1971).
Axes showing endarch maturation and a sympodial vasculature have been classified as Cordaixylon, while those with mesarch leaf traces and a non-sympodial vasculature, as seen in the Joggins specimen (Fig.