THE SEEDLING AND YOUNG PLANT. 



45 



To right and left in 

 Fig. 10 are seen two 

 strands, marked Z, Z, 

 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 

 considering 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 7, Z 2 , Z 3 , 

 etc., in the diagram, 



FIG. 11. Diagram of the course 

 of the vascular bundles as 

 they come down from the 

 leaves into the stem. The 

 horizontal dotted lines rep- 

 resent the levels of sucess- 

 ive leaves ; the triangular 

 white area beneath the up- 

 per letter z is the insertion 

 of a leaf. Each group of 

 bundles form a leaf, as mm, 

 ras, m?, etc. (see text), descends into the stem, and joins with the bun- 

 dles from other leaves after running through several internodes. The 

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



