vm CONTENTS. 



night — Averrlioa : rapid movements of the leaflets— Porlieria : 

 leaflets close when plant kept very dry — Trop^olum : leaves dc 

 not sleep unless well illuminated duiing day — Lupinus : various 

 modes of sleeping — Melilotus: singular movemenrs of terminal 

 leaflet — Trifolium — Desmodiura : rudimentary lateral leaflets, 

 movements of, not developed on young plants, state of their 

 palvini — Cassia : complex movements of the leaflets — Bauhinia: 

 leaves folded at ni.ht — Mimosa pudica: compounded move- 

 ments of leaves, effect of darkness — Mimosa albida, reduced 

 leaflets of — Schranlda: downward movement of the pinnse — 

 Marsilea: the only cryptogam known to sleep — Concluding 

 remarks and summary — Nyctitropism consists of modified cir- 

 cumnutation, regulated by the alternations of light and darkness 

 — Shape of first true leaves Page 317-417 



CHAPTEE VIII. 



Modified Circumsutation : Movemekts excited by Light. 



Distinction between hcliotropism and the effects of light on the 

 periodicity of the movements of leaves — Heliotroplo movements 

 of Beta, Solanum, Zea, and Avena — Heliotropic movements 

 towards an obscure light in Apios, Brassica, Phalaris, Tropseo- 

 lum, and Cassia — Aphellotropic movements of tendrils of Big- 

 nonia — Of flower-peduncles of Cyclamen — Burying of the pods 

 — Heliotropism and apheliotropism modified forms of circumnu- 

 tation — Steps by which one movement is converted into the 

 other — Transversal-heliotropismus or diaheliotropism influenced 

 by epinasty, the weight of the part and apogeotropism — Apogeo- 

 tropism overcome during the middle of the day by diaheliotro- 

 pism — Efiects of the weight of the blades of cotyledons — So- 

 called diurnal sleep — Chlorophyll injured by intense light — 

 Movements to avoid intense light 418-448 



CHAPTEE IX. 



Seksitivfkess of Plants to Light : its transmitted effects. 



Uses of he iotropism — Insectivorous and climbing plants not helic- 

 tropic — Same organ heliotropic at one age and not at another — 

 Extraordinary sensitiveness of some plants to light — The effecta 



