ON CINCHONA. 
255 
Div. 3. — Cinchona barks in which Quinia and Cinchonia 
, are contained in nearly the same stochiometrical pro- 
portions: here are placed the red and Carthagena barks. 
r An arrangement founded on the physical characters of the 
barks will be for the present, perhaps, the most useful, and is 
the one generally followed. In the " Versuch einer Mono- 
graphic der China" of H. Von Bergen (a work which the 
late Dr. Duncan, junior, very justly described as " the most 
perfect specimen of pharmacography" ever published, and 
from which I shall draw very largely in my descriptions of 
the barks,) nine varieties of Cinchona bark are described, 
namely — 
1. China rubra, or red bark. 
2. China Loxa, or crown bark. 
3. China Huanuco, or grey bark. 
4. China regia,or yellow bark of English commerce. 
5. China flava dura, or hard Carthagena bark. 
6. China flava fibrosa, or woody Carthagena bark. 
7. China Huamalies, or rusty bark. 
8. China Jaen, or ash bark. 
9. China pseudo-Loxa, or bastard crown bark. 
I am indebted to the kindness of Von Bergen for illustra- 
tive examples of these and other varieties of Cinchona, by 
which I have been able to identify the species with those 
known in English commerce. 
M. Guibourt, in the third edition of his " Histoire abre'ge'e 
des Drogues Simples," has described no less than thirty- 
seven varieties of Cinchona barks, which he has arranged 
under five heads: — 
1. Grey [or pale] barks. 
2. Yellow barks. 
3. Red barks. 
4. White barks. 
5. False Cinchona barks. 
By an interchange of specimens, M. Guibourt and myself 
have been enabled to determine the synonymes of the barks 
