TABLE OF CONTENTS. XV 

 b. Ligneous Bundles. 



PAGE 



Sect, 149. Normal Ligneous Bundles 493 



„ 1 50. Peculiar Forms 498 



c. Changes of the Tisssues in the Annual Ring. 



„ 151 500 



el. Normal Differences of Successive Zones of Thickening. 



„ 152, Innermost Ring. Medullary Sheath 504 



„ 153. Successive Increase in the Size of the Elements 505 



„ 154. Alburnum and Duramen 507 



e. Individual and Local Deviations. 



„ 155. Differences according to the Thickness of the Annual Ring . • Sn 



„ 156. Rings with Indistinct Limits 513 



„ 157. Individual Variations 514 



f. Differences between Non-equivalent Members. 



„ 158. Stem, Branches, Roots 515 



„ 159. Fleshy Roots 516 



III. The East. 



„ 160. General Considerations jig 



„ 161. Forms of Tissue of the Bast 520 



„ 162. Parenchyma. Sieve-tubes 521 



„ 163. Laticiferous Tubes 525 



„ 164. Secretory Passages and Sacs 525 



„ 165. Sclerenchyma. Bast-fibres 526 



„ 166. Crystal-sacs 529 



„ 167. Variations according to successive Zones, Individuals, &c. . . , 530 



CHAPTER XV. 



Secondary Changes outside the Zone of Thickening. 



Sect. 168. Pith 533 



„ 169. Parts lying outside the Cambial Zone 535 



„ 170. Epidermis ^35 



„ 171. Cortical Parenchyma. Dilatation. Secondary Sclerosis . . . 536 



„ 172. Sieve-tubes, Sclerenchyma, Secretory Sacs 541 



„ 173. Phenomena of Disorganisation 543 



Periderm. 



„ 174. Development and Differentiation of Periderms 544 



„ 175. Superficial Periderm 547 



„ 176. First Internal Formation of Periderm 551 



„ 177. Repeated Internal Periderms. Bark 554 



„ 178. Combination of the different Peridermal Formations in Woody Plants . 558 



„ 179. Lenticels 560 



