is all that can be seen. The boring
instrument, consisting of a double saw, alternately rises and sinks in
the rind of the twig with a gentle, almost imperceptible movement.
Nothing in particular occurs during the process of laying the eggs. The
insect is motionless, and hardly ten minutes elapse between the first
cut of the ovipositor and the filling of the egg-chamber with eggs.

The ovipositor is then withdrawn with methodical deliberation, in order
that it may not be strained or bent. The egg-chamber closes of its own
accord as the woody fibres which have been displaced return to their
position, and the Cigale climbs a little higher, moving upwards in a
straight line, by about the length of its ovipositor. It then makes
another puncture and a fresh chamber for another ten or twelve eggs. In
this way it scales the twig from bottom to top.

These facts being understood, we are able to explain the remarkable
arrangement of the eggs. The openings in the rind of the twig are
practically equidistant, since each time the Cigale moves upward it is
by a given length, namely, that of the ovipositor. Very rapid in flight,
she is a very idle walker. At the most you may see her, on the living
twig from which she is drinking, moving at a slow, almost solemn pace,
to gain a more sunny point close at hand. On the dry twig in which she
deposits her eggs she observes the same formal habits, and even
exaggerates them, in view of the importance of the operation. She moves
as little as possible, just so far as she must in order to avoid running
two adjacent egg-chambers into one. The extent of each movement upwards
is approximately determined by the depth of the perforation.

The apertures are arranged in a straight line when their number is not
very large. Why, indeed, should the insect wander to right or to left
upon a twig which presents the same surface all over? A lover of the
sun, she chooses that side of the twig which is most exposed to it. So
long as she feels the heat, her supreme joy, upon her back, she will
take good care not to change the position which she finds so delightful
for another in which the sun would fall upon her less directly.

The process of depositing the eggs is a lengthy one when it is carried
out entirely on the same twig. Counting ten minutes for each
egg-chamber, the full series of forty would represent a period of six or
seven hours. The sun will of course move through a considerable distance
before