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PHARMACOGNOSY. 
CHAPTER II : POWDERED VEGETABLE 
DRUGS. 
INTRODUCTORY. 
Inasmuch as a large proportion of vegetable drugs 
frequently occur in the market in a more or less pow- 
dered condition, it becomes of first importance to be 
able to identify them as well as to determine their 
quality in this form. Without a microscopical exami- 
nation or chemical analysis this would then depend on 
physical tests alone, as of color, odor and taste. With 
some drugs, tests based on these properties would be of 
more or less value, particularly those containing aro- 
matic and bitter principles ; yet it would soon be found 
that a more detailed examination would be required to 
determine their degree of purity or even to identify 
them with certainty in all cases. 
Classification. — It was not considered desirable to give 
a detailed description of the powder under each drug 
in the chapter on crude drugs, for the reason that the 
identity of the drug as a root, rhizome, bark, etc., is 
lost, and in the examination of a given powder it is 
usually found advantageous to compare it with those 
powders having a similar color. By a careful com- 
parison of the powders of the vegetable drugs, it has 
been found that according to their colors they form 
five main groups, as follows: (1) whitish powders, 
(2) yellowish powders, (3) reddish powders, (4) brown- 
ish powders, (5) greenish powders. These groups are 
then subdivided according to the kinds of ceils and the 
nature of the cell-walls and cell-contents. 
Reagents. — For the rapid differentiation and study of 
the characteristic tissues and cell-contents of the pow- 
