ON CINCHONA. 
325 
purplish brown. Some of the specimens of red bark which I 
received from Von Bergen approach yellow bark in their 
color. The transverse fracture is, in fine quills, smooth; in 
middling quills, somewhat fibrous; in thick quills and flat 
pieces, fibrous and splintery. The taste is strongly bitter, 
somewhat aromatic, but not so intense and persistent as that 
of yellow bark; the odor is feeble, tan-like: the color of the 
powder is faint reddish-brown. 
Botanical history. — The tree which yields red bark of 
commerce is at present unknown. It has been usually sup- 
posed to be obtained from the Cinchona oblongifolia, but this 
is in all probability erroneous. This species of Cinchona 
yields a bark called Quina roxa or Quina Jizahar o roja de 
Santa Fe; and which was supposed to be our red bark. But 
Bergen has examined the bark bearing this name in the collec- 
tion of Ruiz, and finds that it is not our commercial red bark, 
but another kind, known in France by the name of Quinquina 
nova. Moreover, Schrader (who received a piece of the bark 
of the Cinchona oblongifolia from Humboldt) declared it to 
be a new kind; and Guibourt states that the red bark of Mutis, 
which was deposited by Humboldt in the Museum of Natural 
History of Paris, is not commercial red bark, but Quinquina 
nova. To these statements may be added the testimony of 
Ruiz and Pavon, and of Humboldt; the two first of which 
writers state that the Quina roxa is obtained from the Cin- 
chona oblongifolia, but that they do not know the origin of 
Quina colorada (the red bark of commerce;) and Schrader 
states that Humboldt declared he did not know the tree that 
yielded red bark. 
Chemical composition. — Pelletier and Caventou analysed 
the non-verrucous variety of red bark, and found the follow- 
ing constituents: — 
A large quantity of superkinate of quinia and of super- 
kinate of cinchonia. 
Slightly soluble red coloring matter {red cinchonia.) 
Soluble red coloring matter (tannin.) 
Yellow coloring matter. 
