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PHYSIOLOGICAL ACTION OF VENOM OF BLACK SNAKE. 267 
ways, (1) there is a distinct thermogenic effect which is best seen 
if a dilute solution of venom in a piece of sterilised sponge, be 
aseptically inserted under the skin. Under such circumstances 
absorption is very slow, and one obtains a maximum of local, with 
a minimum of constitutional effects, and the temperature is 
invariably raised a few degrees Fahrenheit. 
(2) A diminished production of heat under the influence of the 
profound depression and muscular resolution which usually follow 
the injection of the poison, so that the temperature may often be 
observed to be below 90° just previous to death. 
As found by Sewall! with Crotalus poison, an animal rendered 
resistant to this venom by repeated injections of small non-lethal 
doses, is able to withstand the effects of a quantity which would 
inevitably cause death in an animal not so treated. The injection 
of the lethal dose may under these circumstances be followed by a 
considerable rise in temperature instead of the depression, which 
occurs in animals which have not been accustomed to the poison. 
Calmette? has recorded the same fact from his experiments with 
cobra poison. 
VIIL.—Furrurr Parnotoaicat Errects. 
If the nervous symptoms which result from cobra poisoning are 
recovered from, convalescence is wonderfully abrupt. With the 
exception of the local blood-tinged cedema in the subcutaneous 
tissue, which does occasionally suppurate, there would appear to 
be no further pathological effects. The excretion of the poison by 
the kidneys does not excite pathological changes in these organs, 
aS witnessed by the absence of albuminuria, and the fact that no 
alteration in kidney structure has been observed. 
With the viperine snakes the case is very different. After the 
immediate danger of cardiac and respiratory paralysis has passed, 
the animal suffers from great local and wide spreading hemorrhage 
and edema, which almost invariably suppurates, or becomes gan- 
ane | 
: Journal of Physiology, Vol. viit. 
Ann. de ’ Institut Pasteur, May, 1895. 
