126 OPHIDIANS. 
“ Our own writers* state almost unanimously that the Cro- 
talus is able to kill itself. Without quoting them in full, it 
is enough to add that their experiments were commonly made 
by switching a snake until it turned and struck itself. Death 
is usually described as following within a few moments. 
“ At the close of a series of experiments on warm-blooded 
animals, I made use of some of my largest snakes in the fol- 
lowing manner: 
“ Experiment No.1. Temperature 65° to 75° Fahr. A small 
snake, about twenty-seven inches long, was caught by the 
neck, and its tail placed in its mouth. It bit, but did not 
wound, <A portion of the skin having been removed from 
the back, it was allowed to bite again, and when the fangs 
were fixed in the naked muscles, the upper jaw was violently 
pressed downwards, so as to wound the part deeply. Upon 
the sixth day, the wound was covered with a gray exudation 
such as is usually found upon the healing surface of the 
wounds of serpents. This snake died on the fourteenth day. 
The tissues about the bite were congested, the gall-bladder 
full, mucus in the stomach, the venom-glands dark from 
effused blood. 
“ Experiment No. 2. A large snake was made to bite himself 
twice, in a space near the cloaca where the skin had been re- 
moved. This serpent also died on the fourteenth day. The 
wound was apparently healthy, and not to be distinguished 
from any other wound, except that the muscles about it were a 
little softened. The blood was uncoagulated, but there was 
no other visible lesion of any internal organ. 
“ Experiment No. 3. On the same day a large snake, fifty- 
six inches long, had a small portion of the skin on the back 
* Burnett, p. 323, 
