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Scientific Memoirs by

      It was seized with furious general convulsions after an interval of a
minute and a half and died a minute later.

      Experiment LXXVII. —10-25 A.M. A fowl was bitten by an Echis. It
presently sat down with its beak partly open, and occasionally making conspi-
cuous swallowing movements.

      10-29 A.M. Violent general convulsions, accompanied by loud screaming, set in.

      10-30 A.M. Dead. The blood was of a dull brick-red, rapidly brightening on exposure
                              to air. It was absolutely incoagulable.

      The symptoms of acute intoxication by this venom are clearly, then,
precisely of the same nature as those induced by Daboia-venom, and, from the
data which are on record in regard to the phenomena present in cases of chronic
intoxication following echis-bites, there can be little doubt that the two
materials are in all respects practically identical.

      There is thus conclusive evidence that in two distinct genera of Colubrine
snakes, Naia and Bungarus, the venom possesses essentially identical properties,
and that the same holds good in regard to the venom of two Viperine genera,
Vipera and Echis, but that the colubrine venom is perfectly distinct in property
from the viperine one. This evidence, afforded as it is by the venom of one
or two species of snakes only, is, of course, by no means conclusive, but at the
same time it, at all events, suggests the probability that all snake-venoms are
essentially referable to two groups, each of which includes a number of varieties
differing from one another in quality but not in kind, or, in other words, dis-
tinguished merely by the quantity and not by the nature of the toxic materials
which they contain. In regard to Crotalus-venom, at all events, Dr. Weir
Mitchell's experimental results leave little room to doubt that it is essentially a
viperine venom of the same specific nature as Daboia-venom and, like the latter,
containing two distinct toxic principles, one of which acts as a local and central
nervous irritant, whilst the other gives rise to septic changes in the blood.

       CALCUTTA:

The 19th August 1895.

D. D. CUNNINGHAM.