CONTENTS. xiii 



. Page. 



Development of stomata on etiolated stems 347 



Lenticels of etiolated stems 247 



Epidermal cells of etiolated stems 247 



Collenchymatous layers in etiolated stems 249 



Formation of periderm on woody etiolated stems 249 



Bast fibers of etiolated stems 2:51 



Endoderm, pericycle, sieve tissue, cambium and generative layers of 



etiolated stems 20 



Effects of etiolation on the stele... 21^2 



Etiolation of leaves 2^1, 



Etiolation of leaves of monocotyledons vv^ith parallel venation 255 



Etiolation of petiolate leaves of monocotyledons with open or reticulate 



venation 257 



Effect of etiolation on leaves of dicotyledons 259 



Etiolation of leaves arising from aerial stems 263 



Etiolation of flowers and inflorescences 268 



Effect of etiolation upon spores and sporangia of ferns 378 



Relation of sporophores and sporangia of fungi to light and darkness... 279 



Theories as to the Nature of Etiolation 280 



MoRPHOGENic Influence of Light and Darkness 2S5 



Relation of light and darkness to growth and to differentiation and de- 

 velopment 286 



The stimulative influence of light 288 



Illumination of Etiolated Plants ... 295 



Influence of Etiolation upon Chemical Composition 300 



The Rate and Mode of Growth as Affected by Light and 



Darkness 304 



Index to Contents and to Literature 310 



