422 



SCIENTIFIC AND APPLIED PHARMACOGNOSY 



that of Rhamnus Purshianus, but may be distinguished by the fol- 

 lowing characters: It occurs in quills, transversely curved or flat- 

 tened pieces, the bark usually being thinner. The color is reddish- 

 brown, the bark being uniformly covered with grayish lichens having 

 numerous black apothecia; the inner surface is light or dark brown, 



Fig. 184. Original packages of Cascara Sagrada (Rhamnus Purshianus). 

 After a photograph by Parke, Davis & Co. 



smooth and finely striate; the fracture, odor and taste are similar to 

 Rhamnus Purshianus. The histology of Rhamnus calif ornica closely 

 resembles that of Rhamnus Purshianus. In the former the collen" 

 chymatous cells are larger and the walls somewhat thicker ; the med- 

 ullary rays extend in more or less parallel, wavy rows and are from 



