iv] Solanaceae 59 
of various species and even individuals of the same species is very 
variable. Human beings are most susceptible, followed by the cat and 
dog; the horse is much less so; and the pig, goat, sheep, and rabbit 
are little susceptible to poisoning, even on eating the root the most 
poisonous part (Cornevin). Gohier and others have given over 2 Ib. 
of the green plant to horses without ill effects, and this repeated on three 
days did not cause marked pathological troubles. Hertwig. considered 
large ruminants to be more sensible than horses to the action of Bella- 
donna. It appears to be agreed that small ruminants are very slightly 
susceptible to this plant. Birds are considered almost insensitive, 
while rabbits may be fed for weeks on the leaves without poisoning, as 
also sheep, goats, and pigs. Horses and cattle are more sensitive but 
nevertheless resistant. The poison is no doubt quickly removed by the 
kidneys, since ordinary injection of Belladonna causes the usual symp- 
toms. It is stated that the flesh of rabbits and birds which have eaten 
the plant and have been slaughtered apparently healthy is poisonous 
to man. 
One berry can induce symptoms of human poisoning, and a child 
died after eating only three berries. Mortality in human cases of 
poisoning by Belladonna is given by Kanngiesser as 10 per cent. 
Toxic Principle. Deadly Nightshade is the source of drugs widely 
used in medicine, and its properties as regards man have been exten- 
sively studied. The principal substance present is the alkaloid Hyos- 
cyamine (C 17 H 23 3 N), readily converted into Atropine (C^HgsOgN); 
Scopolamine or Hyoscine (C 17 H 21 4 N), and in smaller quantity Apo- 
atropine, and Belladonine are also present. 
All parts of the plant contain the toxic alkaloids, but in unequal 
degree. The total quantity of the alkaloids is largest in the roots 
(0-4 to 1 per cent.), which in the fresh state contain no Atropine, but 
only Hyoscyamine ; the leaves and fruits contain less of the alkaloids, 
and cultivated plants have been found to be poorer (0-26 per cent.) than 
wild (0-4 per cent). The root has been found to be five times as toxic 
as the berries. Drying does not destroy the poisonous properties. 
Symptoms. In quantities which are not fatal the symptoms are 
nausea, dilatation of pupils, muscular weakness, stumbling, falling, and 
rising only to fall again. These are followed by vertigo, frenzy, and 
coma (more rarely). There is a slight slackening in respiration, and an 
increase in the rapidity of the heart's action. Dysury and constipation 
are observed. 
In fatal quantities the symptoms are more intense and make their 
