PAREIRA BRAVA. • 29 



much the aspect of the climbing steins of Clematis vitalba L., and 

 varied from the thickness of a quill to that of the forefinger, seldom 

 attaining the diameter of an inch. The stems have a light brovrn bark 

 marked longitudinally with shallow furrows and wrinkles, which some- 

 times take a spiral direction. Knots one to three feet apart, sometimes 

 throwing out a branch, also occur. The root is rather darker in colour, 

 but not very different in structure from the stem. 



The fracture of the stem is coarse and fibrous. The transverse sec- 

 tion, whether of stem or root, shows a thickish, corky bark surrounding 

 a light brown wood composed of a number of converging wedg-es (10 to 

 20) of very porous structure, separated by narrow medullary rays. 

 There are no concentric layers of wood,^ nor is the arrangement of the 

 wedges oblique as in many other stems of the order. The drug is 

 inodorous, but has a very bitter taste without sweetness or astrin- 

 gency. 



2. Common False Pareira Brava—VwAer this name we designate 

 the drug which for many years past has been the ordinary Pareira Brava 

 of the shops, and regarded until lately as derived from Cissampelos 

 Pareira L. We have long endeavoured to ascertain, through corre- 

 spondents in Brazil, from what plant it is derived, but without success. 

 We only know that it belongs to the order Menispermacece. 



The drug consists of a ponderous, woody, tortuous stem and root, 

 occurring in pieces from a few inches to a foot or more in length, and 

 from 1 to 4 inches in thickness, coated with a thin, hard, dark brown 

 bark. The pieces are cylindrical, four-sided, or more or less flattened — 

 sometimes even to the extent of becoming ribbon-like. In transverse 

 section^ their structure appears very remarkable. Supposing the piece 

 to be stem, a well-defined pith will be found to occupy the centre of 

 the first-formed wood, which is a column about \ of an inch in 

 diameter. This is succeeded by 10 to 15 or more concentric or 

 oftener eccentric zones, yV to xV ^^ ^^ ^^^^^ wide, each separated 

 from its neighbour by a layer of parenchyme, the outermost being 

 coated with a true bark. In pieces of true root, the pith is reduced to 

 a mere point. 



Sometimes the development of the zones has been so irregular that 

 they have formed themselves entirely on one side of the primitive 

 column, the other being coated with bark. The zones, including the 

 layer, around the pith (if pith is present), are crossed by numerous 

 small medullary rays. These do not run from the centre to the circum- 

 ference, but traverse only their respective zones, on the outside of which 

 they are arched together. 



The drug, when of good quality, has its wood firm, compact, and of 

 a dusky yellowish brown hue, and a well-marked bitter taste. It 

 exhibits under the knife nothing of the close waxy texture seen in the 

 rpot of Chondodendron, but cuts as a tough, fibrous wood. Its decoc- 

 Vn,^ ^''^ .^^^ tinged blue by iodine. It was in this drug that Wiggers in 

 1S39 discovered pelo^dne. 



The drug just described, which is by no means devoid of medicinal 

 power, has of late years been almost entirely supplanted in the market 



_^-^*j^ therefore entirely different to the in Martiua* FZor. Bras. xiiL pars. i. tab. 

 ^ooafigurodasthatofaPamVabyEichler 50, fig, 7. 



