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 with 



Fi<*. 319. Diagram showing the arrangement of the fibro-vasculnr bundles im 22 

 internodes of the stem of Ibtris atnara.-A.ttvT Niigeli. 



other bundles. It is seen, moreover, that there an- 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- 



