Vlll CONTENTS. 



night Averrhoa : rapid movements of the leaflets Porlierja : 

 leaflets close when plant kept very dry Tropaeolum : leaves do 

 not sleep unless well illuminated dining day Lupinus : various 

 modes of sleeping Melilotus : singular movements of terminal 

 leaflet Trifolium Desmodium: rudimentary lateral leaflets, 

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

 pulvini 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 Schrankia: downward movement of the pinnaj 

 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 



CHAPTER VIII. 



MODIFIED CIRCUMNUTATION : MOVEMENTS EXCITED BY LIGHT. 



Distinction between heliotropism nnd the effects of light on the 

 periodicity of the movements of leaves Heliotropic movements 

 of Beta, Solanum, Zea, and Avena Heliotropic movements 

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

 lum, and Cassia Apheliotropic 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 Effects of the weight of the blades of cotyledons So- 

 called diurnal sleep Chlorophyll injured by intense light 

 Movements to avoid intense light 418-448 



CHAPTER IX. 



SENSITIVENESS OF PLANTS TO LIGHT : ITS TRANSMITTED EFFECTS. 



Uses of heliotropism Insectivorous and climbing plants not helio- 

 tropic Same organ heliotropic at one age and not at another 

 Extraordinary sensitiveness of some plants to light The eflecta 



