534 POWDERED VEGETABLE DRUGS 



206. (Fig. 198.) VIBURNUM OPULUS. Cramp Bark. 

 Fl. ex. 60. 



Cranberry tree, E. Wasserholder, G. Obier, Fr. 



The bark of Viburnum opulus L., Caprifoliaceae. 



Pale brown. 



Odorless. 



Bitter, astringent. 



Outer bark of small-celled, thick- walled cork; middle bark of small 

 cells bearing reddish brown coloring matter. Numerous bast fibers 

 and crystal bearing fibers. Some isolated larger, irregular, bent, 

 twisted and branching bast cells. Numerous inner bark parenchyma 

 cells with prismatic crystals. Some larger parenchyma cells with 

 larger crystals. 



Ash 5 per cent. 



May contain an excess of adhering wood fiber. 



