• WordNet 3.6
    • n acrogen any flowerless plant such as a fern (pteridophyte) or moss (bryophyte) in which growth occurs only at the tip of the main stem
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Webster's Revised Unabridged Dictionary
    • n Acrogen (Bot) A plant of the highest class of cryptogams, including the ferns, etc. See Cryptogamia.
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Century Dictionary and Cyclopedia
    • n acrogen An aerogenous plant. The acrogens form a division of the Cryptogamia, distinguished from the thallogens by their habits of growth and mode of impregnation. They have true stems with leafy appendages (excepting the riccias and marchantias), and the embryonic sac is impregnated by the spermatozoids. They are divided into two groups: those composed wholly of cellular tissue, the charas, liverworts, and mosses; and
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Chambers's Twentieth Century Dictionary
    • n Acrogen ak′ro-jen a plant that grows at the top chiefly, as a tree-fern
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Webster's Revised Unabridged Dictionary
Gr. 'a`kros extreme, high + -gen,
Chambers's Twentieth Century Dictionary
Gr. akros, top, genēs, born.


In literature:

No such thing as a petiolate leaf occurs in acrogens, all are attached by a broad base?
"Journals of Travels in Assam, Burma, Bhootan, Afghanistan and TheNeighbouring Countries" by William Griffith
Thirdly, that of the Ferns, Equisetums and Club-mosses (Acrogens).
"The Chain of Life in Geological Time" by Sir J. William Dawson
"The Manual of the Botany of the Northern United States" by Asa Gray