THE SEEDLING AND YOUNG PLANT. 



25 



root would show a more or less loose sheath of cells in 

 addition to and outside this piliferous layer. This is 

 the root-cap, which is a thimble-shaped sheath of looser 

 cells covering the tip of the root as a thimble covers the 



FIG. 5. A. Transverse section of young root under a lens, showing the 

 axis cylinder, a ; epidermis or piliferous layer, e ; and the cortex be- 

 tween. B. The same, more highly magnified : c, cortex ; p, phloem ; 

 a;, xylem ; C. A portion still more highly magnified : pTi, phloem ; 

 j?, pith ; per, pericycle ; sA, sheath (endodermis) ; other letters as 

 before. 



nd of the finger, only we must imagine the extreme tipe 

 of the finger organically connected with the inside of 

 the cap to make the analogy suitable (see Fig. 6). The 



