142 
Journal of Agricultural Research 
Vol. I, No. 2 
other species. The knowledge of the existence of such individual varia¬ 
tions should have an important bearing on the question of the improve¬ 
ment of drug plants by selection and cultivation. 
To show the great variation found among the comparatively limited 
number of plants under observation Table VI is here presented. 
Table) VI .—Range of variation in percentage of alkaloids in the leaves of belladonna 
plants at each stage of growth , at Arlington , Madison , and Bell stations , in different 
years. 
Alkaloidal content of the leaves (per cent). 
Stage of growth. 
Arlington, Va. 
Madison, Wis. 
Bell, Md. 
1910. 
1911. 
1912. 
1911. 
1912. 
1911. 
High. 
Low. 
High. 
Low. 
High. 
Low. 
High. 
Low. 
High. 
Low. 
High. 
Low. 
First picking . 
Second picking . 
Third picking. 
0. 700 
0.334 
0.852 
.879 
•925 
.891 
• 733 
0.303 
. 262 
.277 
•311 
. 200 
0.869 
• 747 
.88 2 
.806 
.678 
0.404 
. 292 
.328 
•359 
. 296 
0.580 
. 820 
. 767 
0.418 
•427 
.419 
0. 500 
• 5 i 9 
0.268 
.316 
0. 823 . 
• 783 
• 750 
0.329 
.28 8 
•395 
Fourth picking . 
Fifth picking . 
Season average . 
Average . 
.766 
.306 
.768 
•353 
.665 
•430 
•452 
.312 
• 707 
• 34 <S 
. 841 
.277 
.792 
•339 
. 708 
•423 
.490 
. 298 
. 766 
■ 339 
From this tabulation it appears that the active principle is more than 
three times as great in the leaves of some plants as in those of others 
at the same period of growth, although the plants are in the same plat 
and therefore grow practically in the same soil and under the same 
climatic conditions. Under such circumstances the existing variation 
can hardly be attributed to anything but the inherent characteristic of 
the individual plant. Much has been written concerning the influence 
of soil and climate on the formation of alkaloids in the plants. Gerrard * 1 
has found that a chalky soil favors the formation of atropin. Cheva¬ 
lier 2 concludes from his experiments with fertilizers that the alkaloidal 
content of certain Solanaceae can be increased by means of nitrates and 
farmyard manures. Ransom and Henderson, 3 however, who are working 
along the line of Chevalier's experiment, have not found thus far that 
artificial manures materially affect the percentage of alkaloids in the 
dried leaf, but note in several cases a large increase in the yield of the 
1 Gerrard, A. W. Op. cit. 
! Chevalier, J. Influence de la culture sur la teneur en alcaloxdes de quelques Solan&es. Compt. Rend. 
Acad. Sci. (Paris), 1.150, p. 344-346,1910. 
1 Ransom, Francis, and Henderson, H. J. Belladonna: the effects of cultivation and fertilizers on the 
growth of the plant and its alkaloidal content. Chemist and Druggist, v. 81, no. 1703, p. 53-55. 191a. 
