46 CINCHONA BARKS. 
of Mutis (p. 48), remain undecided whether it was always really the 
bark of C. succirubra.’ The formerly quite extensive exports of fine 
trunk barks of this Cinchona from Guayaquil have long since 
considerably decreased. On the other hand, branch barks of the 
same from Ceylon and from the peninsula of India, as also from 
the other Cinchona plantations, are brought in ever increasing 
amounts into commerce. 
The American Red Cinchona, in accordance with Howard's 
proposition, was referred in 1857 by Klotzsch and H. Schacht’ to 
C. succirubra. 
For the classification of the Cinchona barks the color was adopt- 
ed asa principal characteristic, until the study of their anatomical 
structure appeared in the foreground. It may be accepted that 
the fundamental color of the barks of one species does not remain 
the same at all periods of life; C. succirubra, e. g., shows that the 
special color first appears with absolute definiteness at an advanced 
age. Younger barks of most species are, as a rule, covered with 
a grayish-white or sometimes brownish or nearly blackish cork, 
which only in the extremes of its color or in the form of its outer 
surface is able to afford points of discrimination. Still more indefi- 
nite and predominatingly brownish is the color of the inner tissue, 
so that mixtures of the most different quill barks taken from the 
twigs or younger trunks bear the general name of Cortex Cincho- 
ne (Chine) fuscus. As of equal signification the usually less ap- 
propriate designation of Cortex Cznchone (Chine) griseus seu 
palhdus is applied, with reference to the external coating, as also 
the appellations, quite common with the French, of Ouinguinas gris 
ou brun, and the English expressions, Pale Cinchona Bark, Gray 
Bark. 
As the most important of the brown varieties, is to be mentioned 
the Cinchona from the district of Huanuco, in central Peru, which 
is exported by way of Lima, and named after these two cities. It 
usually consists of quills, which, after being moistened, are from 1 
to 2 centimeters (34 to 34 inch) in circumference and from 2 to 5 
millimeters (;, to ~ inch) in diameter. Its grayish-brown, and in 
~ general quite bright external surface, is somewhat furrowed longi- 
tudinally, provided with transverse fissures, which are mostly not 
very deep and do not extend over the entire periphery, and often 
still covered with whitish cork. The inner surface is of a bright 
? Compare also therewith, Murray, Apparatus medicaminum, VI (1792), 44. 
° * “On the Origin of the Red Cinchona Bark of Commerce,” Abhandlungen der Akad- 
_ emie der Wissensch, zu Berlin, 1858, pp. 51-78. : 
