mesarch

American  

[mez-ahrk, mes-, mee-zahrk, -sahrk] / ˈmɛz ɑrk, ˈmɛs-, ˈmi zɑrk, -sɑrk /

adjective

1. Botany. (of a primary xylem or root) developing from both the periphery and the center; having the older cells surrounded by the younger cells.

2. Ecology. (of a sere) originating in a mesic habitat.

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mesarch British  

/ ˈmɛsɑːk /

adjective

1. botany (of a xylem strand) having the first-formed xylem surrounded by that formed later, as in fern stems Compare exarch 2 endarch

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Etymology

Origin of mesarch

First recorded in 1890–95; mes- + -arch

Example Sentences

The mesarch structure of the leaf-bundles is met with in a less pronounced form in the flower peduncles of some cycads.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 7 "Gyantse" to "Hallel" by Various

Similarly in the sporophylls of some cycads the bundles are endarch near the base and mesarch near the distal end of the stamen or carpel.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 7 "Gyantse" to "Hallel" by Various