206 TRILLIUM. 



2. A cluster of small angular cells in the center of the 

 section just behind the root-cap, the primary meristem, 

 forming the growing point. 



3. Originating in the primary meristem, an epidermis-like 

 row of cells of the root proper, the dermatogen, which 

 is continuous with the epidermis .of the surface of the 

 root. 



4. The central cylindrical mass of cells, to become the 

 fibro-vascular column, the plerome. 



5. The region of cells between the plerome and dermato- 

 gen or epidermis, to become the cortical portion of the 

 root, the periblem. 



6. The branching root-hairs and their relation to the 

 epidermal cells. 



7. Draw the section, showing the regions above noted. 

 Make a transverse section of the root at its wrinkled 



part. Under low power, notice 



8. The peripheral portion of two or more rows of rounded 

 cells. 



9. The underlying large-celled tissue, with delicate dis- 

 torted walls, often torn in sectioning. 



10. The outer portion of the core, with rounded cells 

 becoming smaller as they lie nearer 



11. The circular axial part of the core, the fibre-vascular 

 bundle, containing several large vessels arranged in 

 four or more short radiating rows. 



Use a high power, and notice 



12. The surface row of cells, the epidermis, slightly or not 

 at all differing from 



13. The cells beneath the epidermis, the hypoderma. 



