442 



BOTANY. 



indicate the nodes and the vertical ranks of leaves) the sin- 

 gle bundles which descend from the leaves are. shown to pass 

 through from ten to twelve internodes before uniting witli 



Fig. 319. Diagram showing the arrangement of the flbro-vascular bundles in 22 

 internodes of the stem of Iberis amara. After Nfigeli. 



other bundles. It is seen, moreover, that there are running 

 through the stem five series of branching bundles, which are 

 not quite vertical, but slightly spiral. In Fig. 320 is shown 

 the appearance of an actual section of the stem taken be- 



