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Show VI CONTENTS. gean hypocotyls-Circumnutation of hypocotyls and epicotyls when erect-Oircumnutation of cotyledons-Pulvini or joints of cotyledons, duration of their activity, rudimentary in O.xalis corniculata, their development-Sensitiveness of cotyledons to light and consequent disturbance of their periodic movcmentsSerH:; itiveness of cotyledons to contact.. Page 67-128 CHAPTER III. SENSITIVENESS OF THE APEX 01!, THE RADICLE TO CONTACT AND TO OTHER IRRITANTS. Manner in which radicles bend when they encounter an obstacle in the soil:__Vicia faba, tips of radicles highly sensitive to contact and other irritants-Etl'ects of too high a temperaturePower of discriminating between objects attached on opposite sides- Tips of secondary radicles sensitive- Pisum, tips of radicles sensitive-Effects of such sensitiveness in overcoming , geotropism- Secondary radicles- Phaseolus, tips of radicles hardly sensitive to contact, but highly sensitive to caustic and to the removal of a slice-Troproolum-Gossypinm-Cucurbita -Rapbanus-~sculus, tip not sensitive to slight contact, bighly sensitive to caustic-Quercus, tip highly sensitive to contactPower of discrimination-Zea, tip highly sensitive, secondary radicles-Sensitiveness of radicles to moist air-Summary of chapter . . 129-200 CHAPTER IV. 'l'HE CIRCUMNU'l'ATING MOVEMENTS OF THE SEVERAL PAHTS Ol~ MATURE PLAN'l'S. Circumnutation of stems: concluding remarks on-Circumnutation of stolons: aid thus afforded in winding amongst the stem::; of surrounding plants-Circumnutation of :flower-stems-Chcumnutation of Dicotyledonous leaves-Singular oscillatory movement of leaves of Dionrea-Leaves of Cannabis sink at nightLeaves of Gymnosperms-Of Monocotyledons-CryptogamsConcluding remarks on the circumnutation of leaves: generally rise in the evening and sink in the morning 201-262 , CONTENTS. vii CHAPTER V. MoDIFIED CmcUMNUTATION: CLillfBING PLANTS· EPrNASTrc AND HYPONASTIC MOVEMENTS. ' Circumnutation modified through innate causes or through the action of external conditions-Innate causes-ClimbinO' plants· similarity of their movements with those of ordin:ry plants; increased amplitude; occasional points of difference-Epinastic growt~ of young leav~s-Hyponastic growth of the hypocotyls and epiCotyls of seedhngs-Hooked tips of climbinO' and other plant~ d~1e to modified circumnutation-Ampelopsis tricuspidata -~m1t~1a Pfundii-Straightening of the tip due to hyponasty~~ I~a~tJc growth and circumnutation of the :flower-peduncles of 'lnfolmm repens and Oxalis carnosa.. Page 263-279 CHAPTER VI. MoDIFIED CIRCUMNUTATION: SLEEP OR NYCTITROPic MoVEMENTs THEIR uSE : SLEEP OF COTYLEDONS. , Preliminary sketch of the sleep or nyctitropic movements of leaves -Presence of pulvini-'l'he lessening of radiation the final cause of nictritropic movements-Manner of trying experiments on leaves of Oxalis, Arachis, Cassia, Melilotus, Lotus and Marsilea, and on the cotyled·ons of Mimosa-Concluding remarks on radiation from leaves-Small differences in the conditions make a gre~~ difference in the result-Description of the nyctitropic p~s1t10n and I?ovements of the cotyledons of various plantsLlst 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 .. 280-316 CHAPTER VII. 1 tfODIFIED CIRCUMNUTATION: NYC'l'l'l'ROPIC OR SLEEP MOVEMENTS OF LEAVES. Jonditions necessary for these movements-List of Genera and Families, which include sleeping plants-Description of tl1e movements in the several Genera-Oxalis: leaflets folded at |