indusium


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Related to indusium: pollen grain, indehiscent, strobilus, sporophyll, indusium griseum

in·du·si·um

 (ĭn-do͞o′zē-əm, -zhē-, -dyo͞o′-)
n. pl. in·du·si·a (-zē-ə, -zhē-ə)
An enclosing membrane, as that covering the sorus of a fern.

[Latin, tunic, perhaps alteration of Greek endusis, dress, from enduein, to sink into, put on : en-, in; see en-2 + duein, to sink.]

indusium

(ɪnˈdjuːzɪəm)
n, pl -sia (-zɪə)
1. (Botany) a membranous outgrowth on the undersurface of fern leaves that covers and protects the developing sporangia
2. (Zoology) an enveloping membrane, such as the amnion
[C18: New Latin, from Latin: tunic, from induere to put on]
inˈdusial adj

in•du•si•um

(ɪnˈdu zi əm, -ʒi əm, -ˈdyu-)

n., pl. -si•a (-zi ə, -ʒi ə)
1. Bot., Mycol. any of several structures having a netlike or skirtlike shape, as the membranous overgrowth covering the sori in ferns.
2. Anat., Zool.
a. an enveloping layer or membrane.
b. a thin layer of gray matter on the corpus callosum.
[1700–10; < New Latin; Latin: kind of tunic]
in•du′si•al, adj.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.indusium - a membrane enclosing and protecting the developing spores especially that covering the sori of a fernindusium - a membrane enclosing and protecting the developing spores especially that covering the sori of a fern
covering, natural covering, cover - a natural object that covers or envelops; "under a covering of dust"; "the fox was flushed from its cover"
sorus - cluster of sporangia usually on underside of a fern frond
References in periodicals archive ?
2007); (5) type of rhizome (RT), 1 = erect or decumbent, 2 = short, stout, compact, 3 = short, horizontal or ascending, 4 = short-creeping, horizontal, 5 = long-creeping, horizontal; determined by field observations and species descriptions of Mickel and Smith (2004); (6) leaf morphology (LM), classifying the leaf as 1 = monomorphic or 2 = dimorphic; (7) leaf thickness (LT); 1 = thin, 2 = medium or 3 = thick; (8) indusium (IN), classified as 1 = present, 2 = absent, and (9) hydathodes (HY) classified as 1 = present or 2 = absent for each specimen (Kluge and Kessler, 2007).
Which of the following is an element: indium, indusium or indumentum?
A popular theory in neuroscience literature, proposed first by David Chamberlain (1) and later by Michael Persinger, (2) is that the indusium griseum plays a functional role in the developing fetus; it is viewed primarily as the embryonic equivalent of the adult hippocampus and secondarily as the sensory homunculus of the fetus.
Rhizomes long, creeping; fronds 60-125 cm long; blades 35-70 cm long, broadly triangular, bipinnate-pinnatifid; rachis winged toward apex; sori round sub-medial; indusium short-lived.
Specimens collected from different seasons were checked to ensure the stability of indusium characters.
Larger pinnae mostly more than 5cm long; rhizome robust: indusium covering top of sorus: Dryopteris
The originally undifferentiated filaments become entrapped in a cup-shaped indusium which triggers their differentiation into akinetes.
Most species of Megalastrum are non-indusiate or have a minute, hair like, and fugacious indusium; in the Andean countries, only four species have a well-developed circular indusium (M.