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Show Vlll CONTENTS. nig:ht-Averrhoa: rapid movements of the leaflets-Porlieria: le;tiets close when plant kept very dry-Tropreolu:U: leave~ do not sleep unless well illuminated during day-Lupmus: var~ous modes of sleeping-Melilotus: singular movements of termmal leaflet-Trifolium-Desmodium: rudimentary lateral leaflets, movements of, not developed on young plants, state of ~h.eir pulvini-Cassia: complex movements of the leaflets-Bauhm1a: leaves folded at night-Mimosa pudica: compounded movements of leaves, effect of darkness-Mimosa albida, 1:educed leaflets of-Schrankia: downward movement of the pmn~Marsilea: the only cryptogam known to sleep-Concludmg remarks and summary-Nyctitropism consists of modified circumnutation reO'ulated by the alternations of light and darkness --Shape of flrst true leaves . •. .. .. .. Page 317-417 CHAPTER VIII. 1\{0DlFIED CIRCUll:lNUT.A.TION: MOVEMENTS EXCITED BY LIGHT. Distinction between heliotropism and the effects of light on the periodicity of the movements of leaves-He~iotro~ic movements of Beta, Solanum, Zea, and Avena-HehotropiC movements towards an obscure light in Apios, Brassica, Phalaris, Tropreolum, and Cassia-Apheliotropic movements of ~endrils of Bignonia- Of flower-peduncles of Cyclamen-:-Burymg of the pods -Heliotropism and apheliotropism modified forms of circumnutation- Steps by which one movement is converted into the other-Transversal-heliotropismus or diaheliotropism influenced by epinasty, the weight of the part and apogeotropism~Ap.ogeotropism overcome during the middle of the day by dlahehotropism- Effects of the weight of the blades of cotyledons-Socalled diurnal sleep-Chlorophyll injured by intense lightMovements to avoid intense light.. . . 418-448 CHAPTER IX. ~ SENSITIVENESS OF PLANTS TO LIGHT : ITS TRANSMITTED EFFECTS. Uses of heliotropism-Insectivorous and climbing plants not heliotropic- Same organ heliotropic at one age and not at anotherExtraordinary sen1:1itiveness of some plants to light-The effectM CONTENTS. IX ?f lig~t ~o not correspond with its intensity-Effects of previous Illu~unatwn-Time required for the action of light-After-effects o~ hght-:-Apogeotropism acts as soon as light fails-Accuracy ~1th ~h1~h plants bend to the light-This dependent on the Illummatwn of one whole side of the part-Localised sensitiveness to light and its transmitted effects-Cotyledons of Phalaris, ~anner of bending-Hesults of the exclusion of light from their t1ps-E~ects .transmitted beneath the surface of the groundLateral Illummation of the tip determines the direction of the curvature of the base-Cotyledons of Avena, c.urvature of basal part due to the illumination of upper part-Similar results with the ~ypocotyls of Brassica and Beta-Radicles of Sinapis apbeliotropic, due to the sensitiveness of their tips-Concluding remarks and summary of chapter-Means by which circumnutation has been converted into heliotropism or apheliotropism Page 449-492 CHAPTER X. MODIFIED CIRCUMNUTATION : MovEMEN'l'S EXCI'l'ED BY GRA VIT .A. TION. Means of observation-Apogeotropism-Cytisus-Verbena-Beta -Gradual conversion of the movement of circumnutation into apogeotropis~ in Rubus, Lilium, Phalaris, A vena, and Brassica -Apogeotrop1sm retarded by heliotropism-Effected by the aiJ of joints or pulvini-Movements of flower-peduncles of OxalisGeneral remarks on apogeotropism-Geotropism-Movements of radicles-Burying of seed-capsules-Use of process-Trifolium subterraneum- Arachis- Amphicarprea- DiageotropismConclusion 493-522 CHAPTER XI. LOCALISED SENSITIVENESS TO GR.A. VITATION, AND ITS TRANSMITTED EFFECTS. Genera~ considerations-Vicia faba, effects of amputating the tips of the radicles-Regeneration of the tips-Effects of a short exposure of the tips to geotropic action and their subsequent amputation-Effects of amputating the tips obliquely-Effects of cauterising the tips-Effects of grease on the tips-Pisum b |