ar less effectually. In this way it
contrives to dig itself a shallow pit. Then, bracing itself against the
wall of the pit, with the aid of wriggling movements which are favoured
by the short, stiff hairs bristling all over its body, the grub changes
its position and plunges into the sand, but still with difficulty.

Apart from a few details, which are of no importance here, we may repeat
this sketch of the Anoxia-grub and we shall have, if the size be at
least quadrupled, a picture of the larva of Oryctes nasicornis, the
monstrous prey of the Garden Scolia. Its general appearance is the same:
there is the same exaggeration of the belly; the same hook-like curve;
the same incapacity for standing on its legs. And as much may be said
of the larva of Scarabaeus pentodon, a fellow-boarder of the Oryctes and
the Cetonia.

CHAPTER 5. THE PROBLEM OF THE SCOLIAE.

Now that all the facts have been set forth, it is time to collate them.
We already know that the Beetle-hunters, the Cerceres (Cf. "The Hunting
Wasps": chapters 1 to 3.--Translator's Note.), prey exclusively on the
Weevils and the Buprestes, that is, on the families whose nervous system
presents a degree of concentration which may be compared with that of
the Scolia's victims. Those predatory insects, working in the open
air, are exempt from the difficulties which their emulators, working
underground, have to overcome. Their movements are free and are directed
by the sense of sight; but their surgery is confronted in another
respect with a most arduous problem.

The victim, a Beetle, is covered at all points with a suit of armour
which the sting is unable to penetrate. The joints alone will allow the
poisoned lancet to pass. Those of the legs do not in any way comply with
the conditions imposed: the result of stinging them would be merely a
partial disorder which far from subduing the insect, would render it
more dangerous by irritating it yet further. A sting in the joint of the
neck is not admissible: it would injure the cervical ganglia and lead
to death, followed by putrefaction. There remains only the joint between
the corselet and the abdomen.

The sting, in entering here, has to abolish all movement with a single
stab, for any movement would imperil the rearing of the larva. The
success of the paralysis, therefore, demands that the motor ganglia,
at least the three thoracic ganglia, shall be packed in close contact
opposite this point. This determines