VEGETABLE POWDERS 



501 



Fig. 181. Ruellia ciliosa roots and rhizomes. This constitutes the most common 

 adulterant of Spigelia marilandica. 



a. Outer parenchyma, two cells with cystoliths. 



b. Sclerenchyma cells. 



c. Parenchyma cells, longitudinal view. 



d. Cork tissue. 



e. Tracheids. 



