ANGELICA 495 



should be stored in tightly closed containers, to which a few drops of 

 chloroform or carbon tetrachloride should be added from time to 

 time, to prevent the development of insects. 



Description. Rhizome upright, nearly cylindrical, usually split 

 into longitudinal pieces, from 5 to 10 cm. in length and from 2 to 3.5 

 cm. in diameter; externally dark brown, upper portion with rem- 

 nants of attached leaves, which are either of a light brown or purplish- 

 red color, more or less annulate from the scars of bud-scales, with a few 

 circular root scars and numerous large fleshy roots; internally light 

 yellow, cortex about 3 mm. in thickness, light brown, having numer- 

 ous radial rows of yellowish or yellowish-red oil canals, wood slightly 

 radiate and porous, pith frequently with large apertures containing 

 larva? or winged insects; odor strongly aromatic; taste sweetish, 

 aromatic and pungent. 



Roots slightly tapering, from 6 to 18 cm. in length and from 3 to 

 10 mm. in diameter; externally grayish-brown to reddish-brown, 

 longitudinally wrinkled and furrowed, with numerous root scars 

 and slender branches; fracture short when dry, tough when damp; 

 internally yellowish, cortex with numerous circles of radiating rows 

 of oil canals containing glistening globules of oil ; wood slightly radiate 

 and porous. 



Inner Structure. A corky layer of thin-walled, reddish-brown 

 cells; phelloderm consisting of several rows of collenchymatous 

 cells; cortex of starch-bearing parenchyma and usually with large 

 diaphragms, due to the separation of the cells in plates from each 

 other in the process of drying; phloem consisting of broad wedges 

 of leptome, bast parenchyma and radiating rows of large oil cavities; 

 the latter are very long, from 0.100 to 0.200 mm. in width, more or 

 less equidistant from each other and the epithelial cells, lining the 

 canals, are usually surrounded by a layer of thick-walled somewhat 

 suberized cells : medullary rays from 3 to 8 cells in width and 10 to 20 

 rows in height; xylem consisting of narrow wood wedges (composed 

 of wide tracheae, having large lenticular simple pores) and starch- 

 bearing parenchyma, the wedges being separated by rather broad, 

 starch-bearing medullary rays; the pith of the rhizome consists 

 of numerous starch-bearing parenchyma and occasional oil canals; 

 the walls of the parenchyma cells, associated with the tracheae, and 

 also the cells of the pith are frequently marked by scalariform per- 

 forations; starch grains numerous, occurring in the parenchyma and 

 cells of the medullary rays in either single or compound grains, the 

 individual grains being spheroidal or polyhedral and varying from 

 0.004 to 0.008 mm. in diameter. 



