PRUNUS VIRGINIANA 



299 



tinct, and on the addition of water developing an odor of benzalde- 

 hyde and hydrocyanic acid; taste astringent, aromatic. 



The bark of the trunk is dark brown and rough externally/ 



Inner Structure. See Fig. 135. 



? fc'MJ 



a 



FIG. 135. Prunus serotina Ehrhart: A, longitudinal section of inner bark, show- 

 ing crystals of calcium oxalate (a), medullary ray cells containing starch 

 (6 and d), and leptome or sieve (c). B, transverse section of stem bark 

 showing cork, probably secondary periderm (a) cells of cortex (6) containing 

 chloroplasts, groups of sclerotic cells (c), compressed leptome in the outer 

 portion of the bast layer (d), medullary ray cells (e), group of sclerotic cells 

 (/), fissures (g) between medullary ray cells and adjacent phloem tissues, 

 cambium zone (i), vessel or trachea in mature wood (k). After Bastin. 



Powder. Light brown; bast fibers and stone cells with much 

 thickened and strongly lignified walls; crystal fibers containing 

 monoclinic prisms and rosette aggregates of calcium oxalate from 

 0.020 to 0.040 mm. in diameter; starch grains nearly spheroidal 

 about 0.003 mm. in diameter. 



Constituents. A cyanogenetic glucoside, identified by Power and 

 Moore as 1-mandelonitrile glucoside, a compound which has been 



