THE WALLFLOWER 



FiQ. 34. A, Diagrammatic transverse section of a diarch root, to 

 show the position of rootlets. B and C, Transverse section 

 of root of Hesperis (allied to Wallflower), to show a rootlet 

 at two stages of development: r.h, root-hairs; ec, cortex; d, 

 cells in process of absorption ; en, endodermis ; pe, pericycle ; 

 co, conjunctive tissue ; ph, phloem ; g, cambium ; x, xylem ; 

 c, calyptrogen of rootlet; p, its periblem ; pi, its plerome. 

 (After Van Tieghem.) B and C magnified about 250. 



