THE SEEDLING AND YOUNG PLANT 



45 



marked I, I, and these 

 run chiefly in what 

 may be called the faces 

 of the five-angled stem ; 

 only, at the node where 

 the leaf we are consi- 

 dering is inserted, they 

 turn in towards the leaf, 

 and eventually they run 

 into the sides of the 

 petiole of the leaf as 

 the so-called ' lateral 

 strands,' or bundles. 



Now, observation 

 shows that these lateral 

 strands (marked I, I 2 , Z 3 , 

 &c., in the diagram, 

 fig. 11) receive contri- 

 butions at successive 



FIG. 11. Diagram of the 

 course of the vascular 

 bundles as they come 

 down from the leaves into 

 the stem. The horizontal 

 dotted lines represent the 

 levels of successive leaves ; 

 the triangular white area 

 beneath the upper letter z 

 is the insertion of a leaf. 

 Each group of bundles 

 from a leaf, as mm, ms, ms, 

 &c. (see text), descends into the stem, and joins with the bundles 

 from other leaves after running through several intemodes. The 

 other letters refer to the bundles from other leaves. (After Frank,) 



