calyptra

American  

[kuh-lip-truh] / kəˈlɪp trə /

noun

Botany.

1. Also called cap.  a hood or hoodlike part, as the lid of the capsule in mosses.

2. a root cap.

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calyptra British  

/ kəˈlɪptrə, kəˈlɪpˌtreɪt /

noun

1. a membranous hood covering the spore-bearing capsule of mosses and liverworts

2. any hoodlike structure, such as a root cap

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calyptra Scientific  

/ kə-lĭp′trə /

1. 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.

2. See root cap

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Other Word Forms

• calyptrate adjective

Etymology

Origin of calyptra

1745–55; < New Latin < Greek kalýptra veil, covering, equivalent to kalýp ( tein ) to veil, cover + -tra noun suffix

Example Sentences

The calyptra buds to form a mature gametophyte.

From Textbooks • Jan. 1, 2015

B, Similar plant with an almost mature sporogonium; s, seta; f, capsule; c, calyptra.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3 "Brescia" to "Bulgaria" by Various

Thallus dichotomous, proliferous, the early divisions linear-oblong, the margins ascending and remotely sinuate, the later divisions linear-palmatifid, coarsely nerved; cells large, hexagonal; involucre ciliate-fringed or lacerate; calyptra smooth, included.—Wet limestones and shales.

From The Manual of the Botany of the Northern United States Including the District East of the Mississippi and North of North Carolina and Tennessee by Gray, Asa

Capsule filling the involucre, circumscissile in the middle, the calyptra persistent at its base.

From The Manual of the Botany of the Northern United States Including the District East of the Mississippi and North of North Carolina and Tennessee by Gray, Asa

Capsules short-pedicelled, or sessile on the thallus, or immersed in its substance, free or connate with the calyptra, globose, at length rupturing irregularly.

From The Manual of the Botany of the Northern United States Including the District East of the Mississippi and North of North Carolina and Tennessee by Gray, Asa