acrogenn.
/ˈakrədʒ(ə)n/, U.S. /ˈækrədʒ(ə)n/ Botany. Now historical and rare.
A cryptogam (flowerless plant) having a distinct perennial stem with the growing point at its extremity, such as a fern or a moss.Contrasted with a ‘thallogen’ (thallophyte), such as a lichen or a fungus, which has no permanent stem.
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the world > plants > part of plant > reproductive part(s) > spore or sporule > cryptogam or plant having spores > [noun] > types of
acrogen1834
endophyte1835
oophore1875
zygophyte1885
oophyte1886
microgametophyte1907
megagametophyte1915
macrogametophyte1931
1834 J. Lindley in Lancet 11 Oct. 94/2 The divisions of monocotyledons, dicotyledons, and acotyledons, characterized by the organs of reproduction, are the same as those of endogens, exogens, and acrogens, characterized by the organs of nutrition.
a1856 H. Miller Testimony of Rocks (1857) i. 12 In the Coal Measures..both the Gymnogens and Acrogens are largely developed.
1884 A. J. Burrows Sci. for Foresters 61 Acrogens, or summit-growers, are flowerless plants which multiply by means of spores.
1902 Canad. Rec. Sci. 8 89 The whole domain of the local Acrogens has yet to be reported on, with the exception of the ferns, horsetails and club-mosses.
1942 Bot. Rev. 8 655 Lindley included all cryptogams (Thallogens and Acrogens) in 25 natural orders as contrasted with 278 for the seed-plants.
This entry has been updated (OED Third Edition, December 2011; most recently modified version published online December 2021).
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n.1834