Doubleness definition of Doubleness in the Free Online Encyclopedia.

Doubleness

in flowers, the expansion of the corolla or corollalike perianth because of an increase in the number of petals. Doubleness is often the result of the transformation into petals of stamens (roses, peonies, ranunculuses, pomegranate) or pistils (Ranunculaceae, Rosaceae, some violets, clover, some petunias). More rarely, doubleness results from the splitting of petals (fuchsia) or stamens (some Caryophyllaceae) or the increase in the number of circles in a simple perianth (some tulips and lilies). Double inflorescences are encountered among the Compositae; these result from the conversion of the interior bisexual flowers into ligulate, usually infertile flowers (dahlia, aster, chrysanthemum) or peripheral ligulate flowers into tubular flowers.

Horticulturalists can induce doubleness by hybridization or by changing the conditions of cultivation (for example, abundant feeding promotes doubleness). Doubleness is often accompanied by profound changes in the organs of the flower. For example, in Primula anthers develop on the ovarian wall and on the stigma; in fuchsias and roses ovules arise on stamens. Incomplete doubleness is most often encountered. Complete doubleness, with all the stamens and pistils converted into petals (such flowers do not yield seeds), rarely occurs. Although viable pollen is formed in double flowers whose extra petals have been formed from stamens, it is located in deeply hidden tissues and is destroyed the moment the flower opens. If gathered in time, the pollen is suitable for artificial pollination. Vegetative reproduction is often used in cultivating double flowers.

REFERENCES

Fedorov, Al. A. Teratologiia i formoobrazovanie u rastenii. Moscow-Leningrad, 1958.
Zhukovskii, P. M. Botanika, 4th ed. Moscow, 1964.

L. V. KUDRIASHOV

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No references found	I only know myself as a human entity; the scene, so to speak, of thoughts and affections; and am sensible of a certain doubleness by which I can stand as remote from myself as from another. Walden & on the Duty of Civil Disobedience by Thoreau, Henry David View in context The voice that said this made sweet music to Maggie; but athwart it there came an urgent, monotonous warning from another voice which she had been learning to obey,--the warning that such interviews implied secrecy; implied doing something she would dread to be discovered in, something that, if discovered, must cause anger and pain; and that the admission of anything so near doubleness would act as a spiritual blight. The Mill on the Floss by Eliot, George View in context	double-theodolite observation double-throw bolt double-throw circuit breaker double-throw switch double-tier partition double-tiered porch double-track tape recorder double-tuned amplifier double-tuned circuit double-tuned detector double-U groove weld double-V groove weld double-wall cofferdam double-wedge cut double-welded joint double-winding synchronous generator double-word addressing double-work double-wythe wall doubled sig Doubleday, Abner Doubleday, Frank Nelson Doubleday, Neltje de Graff doublehand drilling doublehanded saw Doubleness doubler doubles DoubleSpace doublet doublet antenna doublet flow doublet trigger Doubling doubling course doubling dose doubling piece doubling the angle on the bow doubling time doubloon doubly linked list doubly linked ring doubly plunging fold doubly prestressed concrete doubly reinforced concrete doubly ruled surface doubly stochastic matrix Doubs Doubs River doubt douche	Doubleclicking doubled doubled doubled doubled doubled Doubled and Rolled Doubled Haploid Lines Doubled Over In Laughter Doubled Rope Technique doubled sig doubled up doubled up doubled up doubled up Doubleday Doubleday (publisher) Doubleday, Abner Doubleday, Frank Nelson Doubleday, Neltje de Graff Doubledecker Doubledong Doubledong Doubledong Doubleganger Doublegee doublehand drilling doublehanded saw doubleheader doubleheader Doubleness Doubleplusgood Doubleplusgood Doubleplusgood Doubleplusungood Doubleplusungood Doubleplusungoodwise Doubleplusungoodwise doubler doubler doubler doubler doublers doublers doublers doublers doubles doubles doubles doubles doubles doubles up doubles up doubles up doubles up Doubles-entendre Doubles-entendre Doubleshot (coffee) DoubleSpace Doublespace Compressed Volume File doublespeak

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I only know myself as a human entity; the scene, so to speak, of thoughts and affections; and am sensible of a certain doubleness by which I can stand as remote from myself as from another.

Walden & on the Duty of Civil Disobedience by Thoreau, Henry David View in context

The voice that said this made sweet music to Maggie; but athwart it there came an urgent, monotonous warning from another voice which she had been learning to obey,--the warning that such interviews implied secrecy; implied doing something she would dread to be discovered in, something that, if discovered, must cause anger and pain; and that the admission of anything so near doubleness would act as a spiritual blight.

The Mill on the Floss by Eliot, George View in context

double-theodolite observation

double-throw bolt

double-throw circuit breaker

double-throw switch

double-tier partition

double-tiered porch

double-track tape recorder

double-tuned amplifier

double-tuned circuit

double-tuned detector

double-U groove weld