388 TlMEHRI. 
difference could be discovered between the effects of the 
poison of the three snakes mentioned. The average 
quantity of poison introduced by a bite was found to be 
in the case of V. ammodytes "065 gramme, the maximum 
and minimum being "17 and "oi gramme, all the bites 
being after at least three days' abstinence from biting. 
When the bites were repeated one after another, it was 
found that from three to five bites were sufficient to use 
up all the poison. In the case of V. berus only about 
•03 gramme was delivered per bite, while the rattle- 
snake (C. durissimus) delivered ten times as much 
or "3 gramme. 
Regarding the lethal dose for different animals, it was 
found impossible to give it with any approach to scien- 
tific accuracy, for the fresh poison does not always 
contain the same amount of water ; and the inspissated 
substance contains albumen and other indifferent sub- 
stances, the percentage of the active principle being 
entirely unknown. It does not seem that snake-poison 
is to be compared with the most toxic alkaloids, 
as the latter prove much more rapidly fatal even in 
far smaller doses ; though as the percentage of the 
poison principle in snake-poison is entirely unknown, 
not very much emphasis can be placed on this statement. 
It is to be remarked that the young of Mammalia during 
the first four days of lite are less affected by snake- 
poison than adults, even amongst animals which are 
peculiarly susceptible to it : thus while a full-grown 
rabbit will die in from one to five minutes after a bite 
from a large rattlesnake, a rabbit a few days old will 
live for from ten to fifteen minutes after a similat bite, 
and a young kitten will survive for some three hours. 
