thout too much hesitation, the young Scolia settles down
to the wound made by my scalpel, which to the grub represents the wound
whence I have just removed it. It thrusts its neck into the belly of
its prey; and for a couple of days all seems to go well. Then, lo and
behold, the Cetonia turns putrid and the Scolia dies, poisoned by the
ptomaines of the decomposing game! As before, I see it turn brown and
die on the spot, still half inside the toxic corpse.

The fatal issue of my experiment is easily explained. The Cetonia-larva
is alive in every sense. True, I have, by means of bonds, suppressed its
outward movements, in order to provide the nurseling with a quiet meal,
devoid of danger; but it was not in my power to subdue its internal
movements, the quivering of the viscera and muscles irritated by its
forced immobility and by the Scolia's bites. The victim is in possession
of its full power of sensation; and it expresses the pain experienced
as best it may, by contractions. Embarrassed by these tremors, these
twitches of suffering flesh, incommoded at every mouthful, the grub
chews away at random and kills the larva almost as soon as it has
started on it. In a victim paralysed by the regulation sting, the
conditions would be very different. There are no external movements,
nor any internal movements either, when the mandibles bite, because the
victim is insensible. The grub, undisturbed in any way, is then able,
with an unfaltering tooth, to pursue its scientific method of eating.

These marvellous results interested me too much not to inspire me with
fresh devices when I pursued my investigations. Earlier enquiries had
taught me that the larvae of the Digger-wasps are fairly indifferent to
the nature of the game, though the mother always supplies them with the
same diet. I had succeeded in rearing them on a great variety of prey,
without paying regard to their normal fare. I shall return to this
subject later, when I hope to demonstrate its great philosophical
significance. Let us profit by these data and try to discover what
happens when we give the Scolia food which is not properly its own.

I select from my heap of garden-mould, that inexhaustible mine, two
larvae of the Rhinoceros Beetle, Oryctes nasicornis, about one-third
full-grown, so that their size may not be out of proportion to the
Scolia's. It is in fact almost identical with the size of the Cetonia.
I paralyse one of them by giving an injection of amm