DR. EVANS ON THE POISONED SPINES OF THE WEEVER FISH. 361 
two and a half minutes a further fall took place immediately 
preceding complete cardiac failure and death. 
Experiment 2. Cat, -i grm. dried venom, weight 3,400 grm. 
Ether. Immediately after injection marked fall of blood 
pressure and eighteen slow powerful beats in ten seconds, 
i.e., 104 per minute (normal — 192 per minute). This was 
followed by a rise of blood pressure in ten seconds to normal, 
and then another gradual fall with marked slowing oT the 
beats. Thirty-three seconds from first injection the cannula 
was washed out with .86 % sodium chloride solution, and 
the cardiac contractions became gradually small and the 
pressure continuously fell so that two minutes from the 
commencement of experiment the heart had ceased to beat. 
During this time the respiration although affected so as to 
become at first shallow and then every fifteenth breath a deep 
inspiration continued, and there were nine deep inspirations 
during the period of nearly two minutes which elapsed between 
the last cardiac beat and the last respiration. This tracing 
shows in a very convincing way the typical fall of blood 
pressure, the result of an intravenous injection of a venom 
and controverts the theory the cause of death is in the case 
of Weever poison always due to respiratory failure. 
Experiment 3. Cat, weight 3,300 grins. Ether. Injected 
with - i grm. dried venom dissolved in 5 C.C. of an 86 % sodium 
chloride solution, the resulting solution was then centri- 
fugalised and the clear fluid injected into the femoral vein. 
For twenty seconds from the commencement of the injection 
there was a slight fall in blood pressure followed during the 
next fifteen seconds by a slight rise. Then forty seconds 
from the commencement of experiment there was a gradual 
and deep fall of pressure, reaching its lowest point two minutes 
from the commencement. During this fall the cardiac 
pulsations became less strong, the rate being 150 per minute 
as against a normal of 16S per minute. During the first 
thirty seconds the respirations were eight per minute as 
against a normal of nine per minute ; they gradually quickened 
until at the end of the second minute they amounted to from 
fourteen to twelve per minute. Four minutes from the 
VOI„ VIII. 
B B 
