For whatever purpose the sound is produced by the one species, I can
hardly doubt that it serves for the same purpose in the other species;
and I conclude from the threatening gestures made at the same time
by many snakes, that their hissing,--the rattling of the rattle-snake
and of the tail of the Trigonocephalus,--the grating of the scales
of the Echis,--and the dilatation of the hood of the Cobra,--
all subserve the same end, namely, to make them appear terrible
to their enemies.[28]
[24] Mr. J. Mansel Weale, `Nature,' April 27, 1871, p. 508.
[25] `Journal of Researches during the Voyage of the "Beagle,"
' 1845, p. 96. I have compared the rattling thus produced
with that of the Rattle-snake.
[26] See the account by Dr. Anderson, Proc. Zool. Soc. 1871, p. 196.
[27] The `American Naturalist,' Jan. 1872, p. 32. I regret that I cannot
follow Prof. Shaler in believing that the rattle has been developed,
by the aid of natural selection, for the sake of producing sounds which
deceive and attract birds, so that they may serve as prey to the snake.
It seems at first a probable conclusion that venomous snakes,
such as the foregoing, from being already so well defended
by their poison-fangs, would never be attacked by any enemy;
and consequently would have
{note [27] continued} I do not, however, wish to doubt
that the sounds may occasionally subserve this end.
Pages:
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168