240 



BARKS 



(c) The calcium oxalate, 



(d) The characteristic odour. 



Constituents. The bitterness of cusparia bark is due chiefly to 

 angosturin, C 9 H 12 5 , a substance that has been obtained in colourless 

 pulverulent crystals melting at 58, easily soluble in water, alcohol, 

 and ether. The bark also contains a number of alkaloids (2*4 per cent.) , 

 viz. galipine, cusparine, galipoidine, and a fourth which has not yet 

 been closely examined. A glucoside yielding by hydrolysis a fluores- 

 cent substance is also present. By distillation the drug yields about 

 1*5 per cent, of an aromatic volatile oil, the most important constituent 

 of which is the aromatic sesquiterpene alcohol, galipol. Cusparidine 

 and galipidine, alkaloids reported to be present, are probably mixtures 

 of galipine and cusparine. 



FIG. 119. Cusparia bark. Transverse 

 section, showing oil-cells and groups 

 of bast-fibres. Magnified. (Planchon 

 and Collin.) 



FIG. 120. Nux Vomica bark. Trans- 

 verse section, showing band of 

 sclerenchymatous cells. Magnified. 

 (Planchon and Collin.) 



Cusparine, C 20 H 19 NO 3 , forms colourless needles or compact crystalline masses, 

 readily soluble in alcohol, ether, and chloroform ; its salts are sparingly soluble 

 in water. 



Galipine, C 20 H 2r N0 3 , crystallises in colourless needles, but yields deep yellow 

 salts. 



Uses. Cusparia belongs to the group of aromatic bitters. It 

 formerly had a high reputation as a febrifuge and tonic, being preferred 

 to cinchona bark on account of its freedom from astringency. 



Substitutes. The accidental substitution in Hamburg in 1804 of 

 the bark of Strychnos nux-vomica, Linne, for cusparia bark led to 

 several cases of poisoning. Such a substitution or admixture is not 

 likely to occur again, and would moreover be easily detected, as the 

 barks do not bear much resemblance to one another. Nux vomica 

 bark is harder and thicker ; it occurs in small, often recurved, pieces, 

 with dark greyish, yellowish, or rusty-red cork, usually bearing 

 numerous greyish warts. The dark transverse section exhibits under 

 the lens a distinct paler line of sclerenchymatous cells separating the 



