CONTENTS 



VI. Stems 



§119. 

 §120. 

 § 121. 

 §122. 

 § 123. 

 §124. 

 § 125. 

 § 126. 

 § 127. 

 § 128. 

 § 129. 

 § 130. 

 §131. 

 §132. 

 §133. 

 §134. 

 §135. 

 §136. 

 §137. 

 §138. 

 §139. 

 §140. 

 §141. 

 §142. 

 § 143. 

 §144. 

 §145. 

 §146. 

 §147. 

 §148. 

 §149. 

 §150. 

 §151. 

 §152. 

 §153. 



The nature of stems 



Stems are made up of sections or internodes 

 Branches arise at the nodes or joints only 

 Relation of the leaves and branches . 



Leaf traces 



Relation of leaves and flowers . 

 Structure of stems .... 



Uses of stems 



Methods by which firmness is secured 

 Arrangement of dead cells to secure firmness of stems 

 Arrangement of mechanical tissues in a stem of a grass 

 Mechanical tissues in a sunflower stem 

 Mechanical tissues in a cai-nation stem 

 Arrangement of mechanical tissues in a petiole 

 The firmness of plants that become limp when dried 

 Stems as conducting organs 



Upward path of sap 



Path of sap in large trees .... 



Girdling 



Downward path of material from the leaf 



Forces which carry the sap upward through the stem 



Root, or bleeding pressure 



The flow of sap of the sugar maple . 



Dew 



How to cause a plant to form dew at any time 

 Lifting power of leaves and branches 

 Growth of stems .... 



Action of embryonic tissue of a tree 

 Growth in length and diameter 

 Measurement of growth in length 

 Measurement of growth in diameter 



The bark 



Growth of a corn stem 



Nodding or circular movements due to unequal growth 



Length of life 



