XVl LIST OF ILLUSTRATIONS 



FIG. PAGE 



103 Two lots of Squash seedlings of the same age, one grown in light, the 



other in darkness 184 



104 A seedling of Castor-bean 186 



105 Apparatus for the decomposition of starch 186 



106 Air-pump 187 



107 Details of piston of air-pump 188 



108 Air-pump with automatic arrangement to prevent piston from slipping 



back 190 



109 Details of piston of air-pump 190 



110 Arrangement for investigating the power of a leaf to "restore" air 



which has been "vitiated " by a burning candle 191 



111 Arrangement for collecting gas given off by a water-plant in sunlight 192 



112 Apparatus for growing a leaf in air deprived of carbon dioxide 193 



113 Section of leaf of common wild Yellow Mustard 198 



114 Section of leaf of Iris 199 



115 A single chlorophyll grain 201 



116 A single cell of a leaf with chlorophyll grains 202 



117 Arrangement for determining whether leaves give off water vapor 203 



118 Method of inserting a leaf -stalk air-tight in a rubber stopper 205 



1 19 Apparatus for measuring transpiration of a leaf 206 



120 Diagram showing in section and surface view the form and position 



of guard-cells when closed and open 208 



121 Guard-cells and neighboring cells of epidermis 209 



122 Artificial stoma and guard-cells 210 



123 Modification of part of apparatus shown in Fig. 122 211 



124 Acacia leaf, night or sleep position 218 



125 Acacia leaf, day position 218 



126 Leaf mosaic of Ivy Geranium 219 



127 Leaf mosaic of Chestnut t 219 



128 Upright branch of Periwinkle 220 



129 Same branch seen from above 220 



130 Horizontal (trailing) branch from same plant 221 



131 Diagram of cross-section of Squash stem 224 



132 Corn-stalk 225 



133 Stem of Squash (microscopic structure) 227 



134 Cross-section of a bundle of Corn 231 



135 Oak branch (microscopic structure) 232 



136 Bordered pit, cut in half 234 



137 Simple pit, cut in half 234 



138 Pine branch (microscopic structure) 236 



139 Method of injecting a twig by means of the air-pump 237 



140 Arrangement for forcing water through a branch 2:58 



141 Modification of arrangement shown in Fig. 140 240 



