THE WALLFLOWER 65 



end to end, tapering towards the apex of the leaf, and 

 giving off branches on either side. All these branches 

 ramify repeatedly, but always . in the same plane, the 

 successive offshoots becoming finer and finer, until we 

 come to the extremely slender ultimate branchlets, 

 which end blindly within the meshes formed by the 

 larger bundles (see Fig. 24). 



FIG. 24. Part of a section, parallel to the surface, of a leaf 

 of the Wallflower, passing through the palisade paren- 

 chyma, and showing the xylem of the bundles as seen 

 from above. Observe the endings of the bundles within 

 the meshes, p.p, palisade parenchyma ; v b t vascular 

 bundle ; sh, bundle-sheath. The arrows point towards 

 the margin and the midrib of the leaf respectively. 

 Magnified 50. (R. S.) 



The lateral bundles also branch immediately on 

 entering the leaf, and form the bundle-system of the 

 lower part of the lamina. 



The larger vascular bundles of the leaf agree in 

 5 



