LIST OF ILLUSTRATIONS ^yil 



FIG, PAGE 



142 Method of measuring the amount of bleeding from a stump (root pres- 



sure) 243 



142a Buttress formed on the lower side of a branch 248 



143 Terminal part of a growing branch showing the three regions of growth 249 



144 Bud of Brussels Sprouts cut lengthwise 250 



145 Portion of tree trunk near a burl 262 



146 Diagram showing eftect of weight applied to end of a beam 265 



147 Diagram of a girder 266 



148 Diagram showing the g'rder-like arrangement of strengthening tissues 



in a Bulrush 267 



149 Cross-section of a portion of a Cabbage leaf 237 



150 Collenchyma 268 



151 Clematis climbing on an evergreen 271 



152 Behavior of a strip of flower-stalk of Dandelion in water 273 



153 Branch of English Ivy 275 



154 Method of investigating lenticels 279 



155 Method of investigating entrance of air into stem by way of stomata 280 



156 Method of investigating entrance of air into stem by way of stomata 



and lenticels 281 



157 Willow twig suspended in a saturated atmosphere 281 



158 Apparatus for supplying air in a constant stream to an aquarium 283 



159 Arrangement for supplying carbon dioxide to plants growing in water 284 



160 Arrangement for growing water-plants in contact with a bubble of 



carbon dioxide or air ... 285 



161 Cherry blossom cut open to show the parts of the flower 288 



162 Ovary (seed-case) of Oat, with feathery style 290 



163 Branch of the style of Oat, with germinating pollen-grain 290 



164 Embryo sac of a Lily 291 



165 Hanging drop arrangement for the cultivation of pollen-grains 293 



166 Flowers of Gaillardia cut open 303 



167 Flower of Iris, showing how the stigma removes pollen from the bee, etc. 304 



168 Flowers of Partridge berry cut open 305 



169 Flowers of Sage cut open 306 



170 Fruit of Squirting Cucumber in the act of expelling the seeds 321 



171 Clematis fruit, which flies by means of the feathery style 322 



172 Linden fruit, which flies by means of a wing-like bract 322 



173 Hop fruit, which flies by means of a bract 323 



1 74 Maple keys, which fly by means of a wing 323 



175 Burdock head 323 



176 Fruit of Bur Clover 324 



177 Fruit of Beggar's-ticks 324 



178 Fruit of Clotbur 324 



179 Potato which had been allowed to sprout and grow on a dry table 327 



