EXUDATIONS , JUICES, ETC. 
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tains starch, and occasionally the partly developed 
insect, and an outer zone which is porous, lustrous and 
occasionally traversed by a radial canal; odor slight; 
taste strongly astringent. 
Constituents. — The principal constituent is tannin, 
which is found to the extent of 50 to 70 per cent. ; the 
drug also contains gallic acid 2 to 4 per cent., starch 
and resin. 
Allied Products.— Chinese and Japanese galls are 
produced on Rhus semialata by a species of Aphis, and 
are chiefly used in the manufacture of tannic and 
gallic acids. They are irregular, somewhat ovoid, 
more or less tuberculate, grayish brown, very hairy, 
light in weight, brittle, the wall about 1 mm. thick, 
and the cavity containing the remains of numerous 
insects. 
CAMBOGIA (Gamboge). 
A gum - resin obtained from Garciuia Hanburii 
(Fam. GuttifeiTe), a tree indigenous to Siam, Cochin 
China and Cambodia. Spiral incisions are made in 
the bark of the trees, and the gum resin which exudes 
is collected in hollow bamboo stems ; it is then allowed 
to dry slowly, after which the bamboo is removed. It 
is chiefly exported by way of Singapore. 
Description. — In cylindrical pieces, frequently hol- 
low in the center, of variable length, 2 to 5 cm. in 
diameter ; externally grayish orange-brown, longitudi- 
nally striate ; hard ; fracture short, orange-red, waxy 
and somewhat porous; inodorous; taste very acrid. 
The powder is bright yellow, sternutatory, and con- 
tains few or no starch grains; not more than 25 per 
cent should be insoluble in alcohol. 
Constituents. — Gum about 20 per cent.; a resin 
known as cambogic acid about 75 per cent. ; ash 1 to 3 
per cent. 
