Also called cap. a hood or hoodlike part, as the lid of the capsule in mosses.
a root cap.
- ca·lyp·trate [kuh-lip-treyt], /kəˈlɪp treɪt/, adjective
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How to use calyptra in a sentence
The calyptra is half-cleft, and the lid conical and shortly beaked.An Elementary Text-book of the Microscope | John William Griffith
The calyptra (fig. 24) is half-cleft (dimidiate) and very hairy.An Elementary Text-book of the Microscope | John William Griffith
In calyptra Equestris, it has two prominent points, and is described as bi-furcated (fig. 18).A Conchological Manual | George Brettingham Sowerby
The calyptra may be known from Crepidula by the septum, which in the latter is a flat plate reaching half way across the cavity.A Conchological Manual | George Brettingham Sowerby
Involucral leaves coalescent into an oblong truncate hairy tube, blended in our species with the calyptra; perianth none.
British Dictionary definitions for calyptra
a membranous hood covering the spore-bearing capsule of mosses and liverworts
any hoodlike structure, such as a root cap
- calyptrate (kəˈlɪpˌtreɪt), adjective
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
Scientific definitions for calyptra
In some bryophyte plants, a structure that covers the young sporophyte as it develops within the tissues of its gametophyte parent. The calyptra, which consists of a thickening of the archegonium walls, eventually breaks open as the spore capsule grows.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.