216 APPENDIX. 



d. strands of brown sclerenchymatous tissue; two 

 large strands, and many small ones appearing as dots; 



e. the vascular bundles, of various size. 



iii. Cut a transverse section of a piece of rhizome 

 preserved in alcohol, and mount it in glycerine. Examine 

 the parts mentioned above, first with the low and then 

 with the high power. Make a sketch of a single 

 vascular bundle under the low power, shewing the endo- 

 dermis, the phloem, and the xylem. 



Sketch the bundle under the high power, shewing 



a. the brown endodermis ; 



b. the colourless pericycle, often containing numerous 

 small starch grains ; 



c. the protophloem, consisting of flattened cells ; 



d. the phloem vessels (sieve tubes) and the phloem 

 parenchyma ; 



e. the yellow xylem. 



iv. Cut a longitudinal section of a small piece of the 

 rhizome and mount in glycerine. Examine first with the 

 low power and then make sketches under the high power 

 of 



a. the peripheral sclerenchyma, consisting of short 

 brown- walled cells; 



b. the soft parenchyma thin-walled rectangular 

 cells containing starch grains ; 



c. the sclerenchymatous tissue made up of long, 

 narrow, brown, thick-walled cells; 



d. the bundle-sheath ; 



