Gonidium

Definitions

  • Webster's Revised Unabridged Dictionary
    • n Gonidium (Bot) A component cell of the yellowish green layer in certain lichens.
    • n Gonidium (Zool) A special groove or furrow at one or both angles of the mouth of many Anthozoa.
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Century Dictionary and Cyclopedia
    • n gonidium In algol., a reproductive body produced asexually, as a tetraspore or zoöspore. By some authors the term is made to include also the asexual reproductive bodies of fungi and other cryptogams, being in this sense synonymous with conidium.
    • n gonidium In bryology, a cell filled with granules.
    • n gonidium One of the green or chlorophyl-bearing elements of lichens, usually occurring in the thalli in a distinct layer, but sometimes not definitely arranged. They are usually variously rounded cells, distinct or in chains or filaments, and multiply by fission. They were formerly supposed to be produced by the hyphæ of the thallus at their tips; but some recent observers hold that they are formed endogenously in all parts of the lichen and its fruit; others believe that they originate entirely outside and independently of the lichen. The various forms of gonidia are found to resemble closely various forms of fresh-water algæ. The Schwendenerian hypothesis asserts that the gonidia are algæ, and that the fungoid part of the lichen is a fungus parasitic upon them. Several forms have been named, as follows: Eugonidia, or gonidia proper, those having a pure chlorophyl-green color. They are subdivided into haplogonidia, resembling Protoccus; platygondia, depressed and variously membranously connected gonidia; (S) chro-olepogonidia or chrysogonidia, which contain orange granules; confervogonidia, resembling Confervæ.
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Chambers's Twentieth Century Dictionary
    • sing Gonidium a naked or membranous-coated propagative cell produced asexually
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Etymology

Webster's Revised Unabridged Dictionary
NL., fr. Gr. that which generates
Chambers's Twentieth Century Dictionary
Formed from Gr. gonē, generation, seed.

Usage

In literature:

The motile force is imparted to the gonidium by dense rows of waving cilia with which it is completely surrounded.
"Scientific American Supplement, No. 460, October 25, 1884" by Various
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