976 Wisconsin Academy of Sciences, Arts, and Letters. 
1. ) The Pharmacopoeia of 1870 recognized but one species 
of fern (Aspidium Filix-mas) as the source of the official drug, 
hence, the directions: 1 ‘ Take of Male Fern, etc. ’ ’ In the sub¬ 
sequent editions, Aspidium marginale was also recognized as a 
cource of supply. In these editions, the drug is, therefore, 
referred to by the generic name, Aspidium. The species from 
which the official drug is obtained are now referred by botanists 
to the genus Dryopteris. See page 969 under “Drug used, its 
collection, preservation, etc.” 
2. ) Owing to the fact that the drug deteriorates rapidly 
when in the powdered condition, the last three editions of the 
Pharmacopoeia have specified that the rhizomes be preserved 
whole and that they may be reduced to a powder shortly before 
using. For factors causing the deterioration of the drug, see 
under “Drug used, its collection, preservation, etc.” 
3. ) In the last two editions of the Pharmacopoeia, it is di¬ 
rected that the drug be employed in the form of a moderately 
coarse powder (No. 40). In the previous editions, a fine pow¬ 
der (No. 60) was specified. The coarser powder posesses dis¬ 
tinct advantage in that it is better adapted to percolation and 
can be produced with a greater degree of uniformity. 
4. ) It will be observed that the pharmacopoeias of 1870, 1880 
and 1890 directed that the drug be extracted with ether; that 
acetone was the menstruum specified in the Pharmacopoeia of 
1900; and that ether is again directed to be used for this pur¬ 
pose by the present Pharmacopoeia. 
These changes appear to have been made for economic rea¬ 
sons as is evidenced in the following statement by Beringer 
(1916) : “In the Eighth Revision, acetone was directed in place 
of ether, because at that time the former was cheaper. As it 
is now permissable to use denatured alcohol in the manufacture 
of ether, that solvent is made so cheaply that it is again advan¬ 
tageous to use it in place of acetone.” If the comparative cost 
of the two solvents was the factor which induced the Revision 
Committee to make the last change, it is indeed fortunate that 
ether was the cheaper inasmuch as it has proven to be the more 
desirable from a scientific standpoint as well. 
Acetone, although the official menstruum for the preparation 
of this oleoresin for more than a decade, does not appear to 
have been employed for this purpose to any considerable ex- 
