48

Scientific-Memoirs by

     Russell,¹Fayrer, ²Richards, ³Nicholson, ⁴and Hopley ⁵give results of experi-
ments or observations which led them to conclude that the cobra (Naja tripu-
dians) is insensible to its own venom or to that of its fellow species. And Indian
snake-charmers also have come, by experience or tradition, to hold the same belief.

     Breton ⁶and Fayrer ⁷extended to poisonous snakes in general this principle of
insusceptibility.

     And analogous experiments upon scorpions, by Bourne ⁸and others ⁹led to
the conclusion that the poison of a scorpion is quite powerless to kill the same
individual, or another individual of the same, or even of another species.

In favour of susceptibility.

     On the other hand, Professor Weir Mitchell of Philadelphia—whose very
elaborate researches entitle him to the first rank as
an authority on snake-venom—states ¹⁰that he felt
"at liberty to conclude that the animals (crotali).. really died from the
venom (crotalus)." And ¹¹that the venom of the rattlesnake is "poisonous..
to its owner" "as well as to other animals." Mitchell's experiments in this
direction were confined to rattlesnakes, but it is unlikely that the principle involved
should differ materially in the case of the rattlesnake from that of the cobra and
other venomous snakes. Popular reports also credit venomous snakes occasion-
ally with biting themselves with rapidly fatal results. ¹²

Mixed views.

     As intermediate between these antagonistic views may be cited the ap-
parently contradictory opinions of Fayrer and of
Richards. Although Fayrer, in summarizing his con-

  1"An Account of Indian Serpents," Lond. 1796, p. 56. He made one cobra bite another, with the result
that the bitten cobra "remained well." "This experiment was repeated with the like result." This cobra
some days afterwards was bitten in the belly by another cobra, "blood appeared on the wound but no other
consequence followed." While an innocent snake, "a tartutta (Dipsas trigonata?), bitten immediately after
in the same, part, died within two hours."

  2The Thanatophidia of India," Lond. 1872, p. 66 et. seq.

  3Idem, p. 125 et seq.

  4Indian Snakes," 2nd Ed., Madras, 1874, p. 145.

  5Snakes: Curiosities and Wonders of Serpent Life." Lond. 1882, p. 563.

  6Trans. Med. and Phys. Soc. Calcutta, 1826, Vol. I, p. 170. This conclusion, however, was based
upon one solitary experiment on a cobra and a Daboia russellii biting each other.

  7loc. cit. p. 64, "The poisonous snakes are not affected by their own poison." In support of this state-
ment is given, in addition to the experiments on cobras, one case of a 'krait' (Bungarus cœruleus) bitten
by another krait with "no effect" (p. 134); and Richards reports (p. 127, idem) another case in which the
small bitten krait was "found dead" the following morning. But no further experiments seem to
have been made upon kraits, and none upon any of the other species of venomous snakes of India. Re-
garding the effect of venom upon another venomous snake, Fayrer states (p. 73) that the experiment recorded
"seems to prove that the venomous snakes have no power of poisoning each other," and (at p. 64) "in
many of the various experiments I have performed, the Cobra, Daboia and Krait did not appear able to
poison themselves or each other."

  8Proc. Roy. Soc., p. 20 xlii, 1887. He experimented on three species of scorpions found in Madras, with
the view of determining whether scorpions can commit suicide.

  9RAY LANKESTER and others, from experiments made at Cape Town, about six years ago, arrived, I
am informed, at somewhat similar conclusions; but I can find no published record of their results.

  10"Researches on the Physiology and Toxicology of the Venom of the Rattlesnake." (Vol. XII, Smithson.
Contrib.) Washington, 1860, p. 63.

  11Idem, p. 43.

  12Nature, Vol. XXII, p. 40. And FONTANA and MITCHELL refer to the currency of this belief.