PHARMACOGNOSTICAL SYSTEMS. 41 
curred in commerce. To Otto Berg (1815-1866) is due the 
credit of having subjected a large proportion of the crude medi- 
cinal substances employed in Germany, at least all the more 
important ones, to microscopical study. Inthe figurative repre- 
sentation of the anatomical structure of organized vegetable 
substances he was, indeed, preceded by the no less distinguished 
Dutch botanist, Oudemans, 1854-1856. But, in 1865, Berg 
followed with the fifty plates, for the most part very true to 
nature, of his ‘ Anatomischer Atlas zur pharmaceutischen 
Waarenkunde.” 
It is in this direction that pharmacognosy of the present day 
is being developed, on the one hand in practical connec- 
tion with botanical science, and on the other supported by the 
constant progress in organic chemistry. The greater the num- 
ber of active principles of the vegetable kingdom extracted by 
chemical processes, or even built up artificially, the greater the 
changes effected in the pharmaceutical importance of the re- 
spective drugs, for which, indeed, new interest may again be 
specially incited by a more searching botanical examination. 
XII. Pharmacognostical Systems.—The larger number of 
medicinal substances, even by the most exhaustive treatment, 
will only appear of significance from some of the points of view 
that have just been mentioned, while in other respects they may 
present nothing at all worthy of note. It appears of less im- 
portance to treat of these substances in detail than to consider 
the order in which they are classified. They have been grouped 
in special pharmacognostical systems, in a more or less artificial 
manner, by considering either their organological importance, 
or, to a greater extent, their medicinal action and most promi- 
nent chemical constituents, or by utilizing at the same time all 
these principles of division. In opposition hereto, their arrange- 
ment in accordance with the natural families of plants, as fol- 
lowed by botanists, commends itself. The employment of a 
system founded upon this plan is appropriate, because a knowl- 
edge of the families of plants may be presupposed, thus scarcely 
leaving a doubt respecting the proper position of each drug, and 
because it does not admit of the separation of the parts or pro- 
