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SELECTED ARTICLES. 
completely around the bark in the form of rings, the edges of 
which, as well as of the shorter cracks, are a little elevated. 
In some of the fine quills, however, these transverse cracks 
are hardly visible; but we then observe longitudinal furrows. 
On the larger quills the transverse cracks are interrupted, and 
do not form rings, and are not set so closely together. Some 
of the thicker quills have occasionally almost the roughness 
of a grater; and occasionally pieces are met with having knots 
or warts. The color of the external surface of Crown bark 
depends principally on that of the crustaceous lichens. Gray, 
or grayish brown, may be taken as the predominating tint: 
the thin quills are mostly slate, ash, or roe gray. The larger 
quills vary still more, and, in addition to the colors now men- 
tioned, they are sometimes blackish gray, — even passing, in 
places, into liver brown. The inner surface of Loxa bark is 
smooth with small irregular longitudinal fibres observed 
thereon: its general color is cinnamon brown. The trans- 
verse fracture of small quills is even, but of the larger and 
and coarser ones, fibrous. The powder of Loxa bark is of a 
deep cinnamon brown color. The odour of this bark is like 
that of tan; its taste astringent, bitter, and somewhat aromatic # 
Botanical history. — Cascarilla Jina de Uritusinga, or 
genuine Loxa bark, is admitted by most writers to be obtain- 
ed from the Cinchona condaminae. It has, however, been 
supposed that this tree, which is said to be comparatively 
scarce, could not yield all the Loxa bark of commerce; and 
hence the latter has been referred to some other species, and 
the C. scrobiculata has been usually fixed on, in consequence 
of a remark made by Humboldt, that the young barks of these 
two species are hardly distinguishable in commerce. Various 
arguments, however, are advanced by Bergen against this no- 
tion, and he declares himself in favor of the C. condaminea, 
as the mother plant of Loxa bark. One fact he adduces de- 
serves especial attention: the lower part of the branch of the 
C. condaminea, represented in the tenth plate of the first 
volume of the " Plantes Equinoxiales" actually presents 
