CORTEX ANGOSTURA. ANGOSTURA BARK. 171 



St. Hilare; Bonplandia trifoliata, Wildenow (nat. ord. 

 CuspartccE). 



The tree attains a height of from 4 to 5 m. It is found 

 in the mountains of Venezuela in the neighborhood of the 

 source of the Orinoco River. The drug enters commerce 

 by way of Trinidad. 



Description. — Tbe bark comes in irregular, usually 

 slightly curved pieces of various lengths and of a thickness 

 of from I to 3 mm. The outer surface is mostly covered 

 by a spong>% yellowish- white cork, w^arty and somewhat 

 irregularly marked. The bark within is of a reddish- 

 brown color, light, hard and brittle, in thin laminae 

 which often show a shingle-like overlapping appearance 

 on the under side. The fracture is sharp, showing 

 glistening calcium oxalate crystals on the broken sur- 

 faces. On maceration in water the bark swells up. The 

 odor is disagreeably aromatic, the taste aromatic, sharp, 

 and bitter. 



A cross-section shows three distinct zones. The outer 

 light yellowish periderm, the innermost brownish bast 

 region, which is interrupted by the sharp-pointed medul- 

 lary rays penetrating into the shining light middle bark. 

 The periderm consists largely of thin- walled, almost. 

 cubical cells, between which there may at times be found 

 some stone cells. (Marme.) 



Between the thin-walled parenchyma cells of the outer 

 bark single stone cells lie scattered; also many oil cells, 

 which last are larger than the parenchymatic cells, and 

 contain, in fresh condition, yellowish oil or resin. In this 

 same general region many crystal sacs containing raphides 

 may also be found. 



The inner bark contains many parenchymatic cells 

 which contain starch and also crystals. In the inner bark 

 there are also the phloem elements, sieve tubes and bast 

 fibres. The bast fibres are arranged in small bundles. 

 The medullary rays are two or three cells wide, but 



