LIST OF ILLUSTRATIONS. XIX 



FIG. PAGE 



22 Apparatus for demonstrating the hygroscopic properties of 



the awn of Stipa ........ 114 



23 Diagram illustrating the use of turgescent tissue in De Vries' 



experiments on isotonic coefficients ..... 126 



24 Tracings from split portions of the hypocotyl of Ricinus used 



in experiments on isotonic coefficients .... 127 



25 Pfeffer's gypsum method .... 132 



26 Arrangement for demonstrating that a turgesceut shoot loses 



rigidity when bent .... ... 139 



27 Micrometer-screw used in growth experiments . . . 151 



28 Recording auxanometer ........ 154 



29 Method of using the auxanometer-lever . . . 158 



30 Tracing illustrating the effect of an increase of temperature 



on growth ... 160 



31 Hanging writer for recording geotropic or other movements 



on a revolving drum ..... . 172 



32 [Omitted in Edition in.] 



33 Curvature of roots produced by small pieces of card attached 



to the tips ....... 177 



34 Drooping of laurel leaves in a frost . . . 179 



35 A twig of Veronica salicifolia exposed to oblique illumination 184 



36 The klinostat .... . 186 



37 Section showing part of the mechanism of the klinostat . 188 



38 A seedling Cucurbita which has germinated on the klinostat ; 



showing the frill-like growth of the heel or peg . . 193 



39 Diageotropism of the flower of Narcissus poeticus . . 195 



40 Leaves of clover in the day and night position . . 222 



41 The sleep-movements of Mimosa recorded on a drum by 



means of a hanging writer .... . 223 



42 Paraheliotropic movement in Averrhoa bilimbi . . 225 



43 Diagram representing the circumnutation of a cabbage- 



seedling .... . . 223 



44 Leaf of Desrnodium gyrans ... . 232 



45 Apparatus for distillation under reduced pressure . . 246 



