BOTANIC MATERIA MEDICA, 281 
EXCRESENTIA, MEDULH, TRICHOMES, 
GLANDULA, ET FECULA—EXCRES- 
CENCES, PITHS, HAIRS, GLANDS, 
AND STARCHES. 
These constitute a class of drugs differing 
in all respects from those already described, 
and will require especial attention, as many of 
them are well-known remedies, whilst the 
starches should claim an earnest investigation 
from the fact that they exist abundantly in the 
vegetable kingdom, and play an important part 
as an article of food in the animal economy. 
Quercus Infectoria, Quercus Lusitanica, the 
Gall or Dyer’s Oak.—Natural order Cupuliferz. 
This stunted tree is a native of Asia Minor, 
rarely exceeds 8 feet in height, and resembles 
in its foliage the oaks of this country, but its 
fruit is not in clusters—which is the case with 
many of our native oaks—but exists as a solitary 
acorn. Itis from this tree we obtain the gall 
of commerce. The gall-nut is an excrescence, 
and is formed by the female species of cynips 
piercing the buds of the tree (quercus infectoria) 
and therein depositing their eggs; around the 
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