358 



SUBTERRANEAN ORGANS 



the characters given though roots that are dark internally and not 

 starchy often contain high percentages of alkaloid. 



Notwithstanding the fact that the preparations of belladonna root 

 are standardised, the official description is framed so as to exclude 

 such old or partially exhausted roots. 



The root has an odour recalling liquorice root, and a slightly bitter 

 taste. 



FIG. 186. Belladonna root, a, portion of young 

 root, natural size ; b, transverse section of the 

 same, magnified ; c, transverse section of the 

 upper part of the root, magnified. (Holmes). 



The student should carefully observe 



(a) The firm, plump appearance of typical belladonna root, 



(b) The short, mealy fracture, 



(c) The dark cambium line, and distribution of the groups of 



vessels and fibres ; 



and should compare the root with 



(i) Elecampane root, in which oil glands are present, and the 



groups of vessels inconspicuous, 



(ii) Scammony root (small pieces), which have a very 

 characteristic structure, 



