The Collaborative International Dictionary
Nyctitropic \Nyc`ti*trop"ic\, a. [From Gr. ny`x, nykto`s, night + ? turning.] (Bot.) Turning or bending at night into special positions.
Note: Nyctitropic movements of plants usually consist in a folding or drooping of the leaves, the advantage being in lessening the radiation of heat.
Wiktionary
a. (context botany English) Turning or bending at night into special positions.
Usage examples of "nyctitropic".
Preliminary sketch of the sleep or nyctitropic movements of leaves--Presence of pulvini--The lessening of radiation the final cause of nyctitropic movements--Manner of trying experiments on leaves of Oxalis, Arachis, Cassia, Melilotus, Lotus and Marsilea and on the cotyledons of Mimosa--Concluding remarks on radiation from leaves--Small differences in the conditions make a great difference in the result Description of the nyctitropic position and movements of the cotyledons of various plants--List of species--Concluding remarks--Independence of the nyctitropic movements of the leaves and cotyledons of the same species--Reasons for believing that the movements have been acquired for a special purpose.
Preliminary sketch of the sleep or nyctitropic movements of leaves--Presence of pulvini--The lessening of radiation the final cause of nyctitropic movements--Manner of trying experiments on leaves of Oxalis, Arachis, Cassia, Melilotus, Lotus and Marsilea and on the cotyledons of Mimosa--Concluding remarks on radiation from leaves--Small differences in the conditions make a great difference in the result Description of the nyctitropic position and movements of the cotyledons of various plants--List of species--Concluding remarks--Independence of the nyctitropic movements of the leaves and cotyledons of the same species--Reasons for believing that the movements have been acquired for a special purpose.
Although we can see how the slight periodical movements of leaves in a vertical plane could be easily converted into the greater yet simple nyctitropic movements, we do not at present know by what graduated steps the more complex movements, effected by the torsion of the pulvini, have been acquired.
Pancratium littorale, movement of leaves, 255 Paraheliotropism, or diurnal sleep of leaves, 445 Passiflora gracilis, circumnutation and nyctitropic movement of leaves, 383, 384 --, apogeotropic movement of tendrils, 510 --, sensitiveness of tendrils, 550 Pelargonium zonale, circumnutation of stem, 203 --, and downward movement of young leaf, 232, 233, 269 Petioles, the rising of beneficial to plant at night, 402 Petunia violacea, downward movement and circumnutation of very young leaf, 248, 249, 269.
Canna Warscewiczii, circumnutation of plumules, 58, 59 --, of leaf, 252 Cannabis sativa, movements of leaves, 250 --, nocturnal movements of cotyledons, 307 Cannabis sativa, sinking of the young leaves at night, 444 Cassia, nyctitropic movement of leaves, 369 Cassia Barclayana, nocturnal movement of leaves, 372 --, slight movement of leaflets, 401 -- calliantha, uninjured by exposure at night, 289, n.
CASSIA--CRINUM Cassia pubescens, uninjured by exposure at night, 293 --, sleep of cotyledons, 308 --, nyctitropic movement of leaves, 371 --, circumnutating movement of leaves, 372 --, nyctitropic movement of petioles, 400 --, diameter of plant at night, 402 -- sp.
Porlieria hygrometrica, circumnutation and nyctitropic movements of petiole of leaf, 335, 336 --, effect of watering, 336338 --, leaflets closed during the day, 413 Portulaca oleracea, effect of Aecidium on, 189 Primula Sinensis, conjoint circumnutation of hypocotyl and cotyledon, 45, 46 Pringsheim on the injury to chlorophyll, 446 Prosopis, nyctitropic movements of leaflets, 374 Psoralea acaulis, nocturnal movements of leaflets, 354 Pteris aquilina, rachis of, 86 Pulvini, or joints.
Oxalis acetosella: circumnutation and nyctitropic movements of a nearly fullgrown leaf, with filament attached to the midrib of one of the leaflets.
The socalled sleep or nyctitropic movements of leaves are determined by the daily alternations of light and darkness.
Ordinary circumnutation is converted into a nyctitropic movement, firstly by an increase in its amplitude, but not to so great a degree as in the case of climbing plants, and secondly by its being rendered periodic in relation to the alternations of day and night.
Maranta arundinacea, nyctitropic movement of leaves, 389391 --, after much agitation do not sleep, 319 Marsilia quadrifoliata, effect of radiation at night, 292 --, circumnutation and nyctitropic movement of leaflets, 392394 --, rate of movement, 404 Martins, on radiation at night, 284, n.