384 POISONS : THEIR EFFECTS AND DETECTION. [§ 450 . 
Seeds of the Common or 
White Datura. 
(1) Outline angular. 
(2) Attached to the placenta by 
a large, white, fleshy mass separat¬ 
ing easily, leaving a deep furrow 
along half the length of the seed’s 
concave border. 
(3) Surface scabrous, almost 
reticulate, except on the two com¬ 
pressed sides, where it has become 
almost glaucous from pressure of 
the neighbouring seeds. 
(4) Convex border thick and 
bulged, with a longitudinal depres¬ 
sion between the bulgings, caused 
by the compression of the two sides. 
(5) A suitable section shows the 
embryo curved and twisted in the 
fleshy albumen. 
(6) The taste of the datura 
seeds is very feebly bitter. The 
watery decoction causes dilatation 
of the pupil. 
Seeds of Capsicum. 
Outline rounded. 
Attached to the placenta by 
a cord from a prominence on the 
concave border of the seed. 
Uniformly scabrous, the sides 
being equally rough with the 
borders. 
Convex border thickened, but 
uniformly rounded. 
The embryo, exposed by a suit¬ 
able section, is seen to resemble in 
outline very closely the figure 6. 
The taste of capsicum is pun¬ 
gent ; a decoction irritates the eye 
much, but does not cause dilata¬ 
tion of the pupil. 
The identity of the active principle in both the datura and bella¬ 
donna tribes is now completely established. 1 
§ 450. Pharmaceutical Preparations. — (a) Belladonna Leaves .—The 
B.P. method of ascertaining the amount of alkaloids in belladonna 
leaves is as follows :—Into a small stoppered glass percolator provided 
with a glass tap and suitably plugged with cotton-wool, introduce 
10 grms. of belladonna leaves in No. 60 powder and 50 millilitres of a 
mixture of chloroform 1 volume and ether 4 volumes. Shake, set aside 
for ten minutes, then add 2 millilitres of solution of ammonia diluted 
with 3 millilitres of water, and set aside for one hour, shaking frequently. 
Then allow percolation to proceed slowly, receiving the percolate in a 
separator containing 6 millilitres of N/l solution of sulphuric acid diluted 
with 20 millilitres of water. When the liquid ceases to pass, continue the 
percolation with a further 50 millilitres or more of the ether-chloroform 
mixture, added in small quantities, until the leaves are exhausted. Shake 
the separator well, and after separation draw off the acid liquid into a 
second separator. Repeat the extraction of the ether-chloroform solution 
1 See a research by Ernst Schmidt, “ Ueber die Alkaloide der Belladonna-Wurzel 
u. des Stechapfel-Samens,” Lieb. Anna!., Bd. ccviii., 1881. 
