646 NON-SUSCEPTIBILITY OF THE HEDGEHOG TO POISONS. 
substances experimented on, the only ones that produce 
anaesthesia. 2. Amylene does not produce stupefaction, 
unless the quantity of air with which it is diluted be very 
small ; but then it acts upon the animal economy, and espe- 
cially upon the respiratory organs, in a manner which may 
produce dangerous effects. 3. Chloroform has all the ad- 
vantages of amylene, without the evils which accompany the 
use of the latter. 4. None of the substances above-men- 
tioned produce anaesthesia, whether local or general, when 
applied to any peculiar part of the body by injection under 
the skin.” 
A SINGULAR CONCRETION FOUND IN THE ILEUM OF A 
COW. 
Mr. Bovett, a few days since, placed in our hands a mass, 
which at first sight very much resembled fragments of a snake 
that had become petrified. This opinion was shared in 
by others in common with ourselves. He, however, in- 
formed us that it was taken by his father from the ileum of a 
cow, just as this gut makes its last curvature, and was lodged 
in a sac that it had formed for itself. Upon examination, it was 
found to be coated with the phosphates. Its size was about 
that of the fist. A portion having the soluble salts re- 
moved from it bv means of an acid, the remaining fibrous 
matter, under the microscope, showed it to be made up of 
wool. The conjecture, therefore, is that it is part of a 
stocking which the animal had swallowed, and by retention 
it had become covered with the earthy salts above named. 
NON-SUSCEPTIBILITY OF THE HEDGEHOG TO THE 
INFLUENCE OF POISONS. 
Scarcely any poison will act on the hedgehog. Pallas 
gave to one a hundred cantharides, which he seemed to re- 
lish very much, and suffered no inconvenience whatever 
from them. Lassy caused one to be bitten by a viper several 
times, without any effect following. And Mr. Cuthbert 
Johnson states that prussic acid, arsenic, opium, and corro- 
sive sublimate, have each been given to this animal, without 
producing the slightest action upon him. 
