962 Wisconsin Academy of Sciences , Arts, and Letters . 
of aspidium and cnbeb. No tests of this, or, as a matter of fact, 
of any kind have been included in the United States Phar¬ 
macopoeia. It is thought, however, that if interest in these prep¬ 
arations could be awakened in this country, the need of sim¬ 
ilar precautions with respect to all of the official oleoresins would 
become apparent. 
Qualitative Tests: 
Inasmuch as the common physical properties, such as odor, 
taste and appearance, are very characteristic of the oleoresins, 
it is hardly necessary to resort to other means for their identi¬ 
fication. It appears, however, that the use of the so-called 
false cubebs in the preparation of the oleoresin of cubeb has 
made necessary a more certain method of identification. Such 
a method, based on the red color produced when concentrated 
sulphuric acid is added to the oleoresin prepared from the gen¬ 
uine fruit, 1 ) has, therefore, been given in most of the late Eur¬ 
opean pharmacopoeias. Likewise, the use of other species of 
fern in the preparation of the oleoresin of aspidium caused a 
qualitative test for this preparation to be included in the late 
editions of the Austrian, Hungarian and Netherlands phar¬ 
macopoeias. For the details of these methods, see qualitative 
tests under the respective oleoresins. 
Quantitative Tests: 
On the whole, very little has been done in the past toward 
developing quantitative methods for the evaluation of the oleo¬ 
resins. This condition is perhaps due, for the main part, to an 
imperfect knowledge of the chemistry of most of these prepara¬ 
tions, as well as to the lack of exact information concerning the 
constituents of therapeutic value. In the case of the oleoresin 
of aspidium, however, the therapeutic value of the preparation 
has been shown to depend upon a number of acid constituents, 
the quantity present varying through natural and artificial causes. 
As a result, various methods 2 ) for the determination of the total 
acid content have been devised and are in use at the present 
time, a modification of the original method of Fromme being 
officially recognized in the late edition of the British and Swiss 
1 Dekker states that the so-called false cubebs give a yellow color with 
concentrated sulphuric acid. Pharm. Ztg. (1912), 84, p. 845. 
2 See under oleoresin of aspidium. 
