[in-doo-zee-uh m, -zhee-uh m, -dyoo-]
- Botany, Mycology. any of several structures having a netlike or skirtlike shape, as the membranous overgrowth covering the sori in ferns.
- Anatomy, Zoology.
- an enveloping layer or membrane.
- a thin layer of gray matter on the corpus callosum.
Origin of indusium
1700–10; < New Latin; Latin: kind of tunic, perhaps < Greek éndys(is) dressing, dress (endý(ein) to put on + -sis -sis) + Latin -ium, for Greek -ion noun suffix
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for indusium
The indusium arises from a vein to which the sorus is attached.
Thus it is proper to describe the shape of the indusium as peltate.
The sori are narrow, and when young are covered with an indusium.
The sorus is circular and is covered with an indusium which is notched or kidney-shaped.
The indusium is orbicular-reniform, and almost always smooth.Beautiful Ferns
Daniel Cady Eaton
- a membranous outgrowth on the undersurface of fern leaves that covers and protects the developing sporangia
- an enveloping membrane, such as the amnion
C18: New Latin, from Latin: tunic, from induere to put on
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- A thin membrane covering the sorus of a fern. The indusium often shrivels away when spores are ready to be dispersed. Also called fruitcover
- A cuplike structure fringed with hairs and located at the top of the style in flowers of the family Goodeniaceae (which includes the garden flowers lobelia and scaevola). Pollen is deposited into the indusium by the anthers of the same flower and, as the style grows, carried up for dispersal by pollinating insects.
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