CORTEX BIBIRU. 535 



CORTEX BIBIRU. 



Cortex Nectandrce ; Greenheart Bark, Bibiru or Bebeeru Bark. 



Botanical Origin — Nectandra Rodicei Schomburgk — The Bibiru 

 or Greenheart is a hirge foi*est tree,^ growing on rocky soils in British 

 Guiana, twenty to fifty miles inland. It is found in abundance on the 

 hill sides which skirt the rivers Essequibo, Cuyuni, Demerara, Pomeroon 

 and Berbice. The tree attains a height of 80 to 90 feet, with an 

 undivided erect trunk, furnishing an excellent timber which is ranked 

 in England as one of the eight first-class woods for shipbuilding, and is 

 to be had in beams of from 00 to 70 feet long. 



History — In 17G9 Bancroft, in his Histoi'y of Guiana, called 

 att^ention to the excellent timber afforded by the Greenheart or Sipeira. 

 About the year 1835 it became known that Hugh Rodie, a navy 

 surgeon who had settled in Demerara some twenty years previously, had 

 discovered an alkaloid of considerable efiicacy as a febrifuge, in the bark 

 of this tree.- In 1843 this alkaloid, to which Rodie had given the name 

 Bebeerine, was examined by Dr. Douglas Maclagan ; and the following 

 year the tree was described by Schomburgk under the name of 

 Nectandra Rodicei.^ 



Description — Greenheart bark occurs in long heavy fiat pieces, not 

 unfrequently 4 inches broad and I'o of an inch thick, externally of a 

 light greyish brown, with the inner surface of a more uniform cinnamon 

 hue and with strong longitudinal strite. It is hard and brittle ; the 

 fracture coarse-grained, slightly foliaceous, and only fibrous in the inner 

 layer. The grey suberous coat is always thin, often forming small warts, 

 and leaving when removed longitudinal depressions analogous to the 

 digital fiirrovjs of Flat Calisaya Bark (p. 353), but mostly longer. 

 Greenheart bark has a strong bitter taste, but is not aromatic. Its 

 watery infusion is of a very pale cinnamon brown. 



Microscopic Structure — The general features of this bark are 

 very uniform, almost the whole tissue having been changed into thick- 

 walled cells. Even the cells of the corky layer show secondary deposits ; 

 the primary envelope has entirely disappeared, and no transition from 

 the suberous coat to liber is obvious. 



The prevalent forms of the tissue are the stone-cells and very short 

 liber-fibres, intersected by small medullajy rays and crossed transversely 

 by parenchyme or small prosenchyme cells with walls a little less 

 thickened, so as to appear in a transverse section as irregular squares 

 or groups. The only cells of a peculiar character are the sharp-pointed 

 fibres of the inner liber, which are curiously saw-shaped, being provided 

 with numerous protuberances and sinuosities. 



The very small lumen of the thick-walled cells contains a dark 

 brown mass which is coloured greenish-black by sulphate of iron ; the 

 same coloration takes place throughout the less dense tissue surround- 



' Fig. in Bentley and Trimen's Medic. former a substitute for Cinchona, the latter 



Plants, part 26 (1877). frr Sulphate of Quinine.— Edinburgh Med. 



^Halliday, On the Bebeeru tree of British and Surg. Journ. vol xl. 18.S5. 

 Guiana, and Sulphate of Bebeerine, the * Hooker's J< urn. ofBot. 1844. 624. 



