hindrance. The bottom of the well, better wrought than the
rest and ceiled with the aid of an adhesive fluid which holds the fine
sawdust of the stopper in place, is a thing of the present; it is the
nymphosis-chamber.

A second Buprestis, _Chrysobothrys chrysostigma_, likewise an
exploiter of the cherry-tree, between the wood and the bark, although
more vigorous, expends less labour on its preparations. Its chamber,
with modestly varnished walls, is merely an expanded extension of the
ordinary gallery. The grub, disinclined for persistent labour, does
not bore the wood. It confines itself to hollowing a slanting dug-out
in the bark, without touching the surface layer, through which the
insect will have to gnaw its own way.

Thus each species displays special methods, tricks of the trade which
cannot be explained merely by reference to its tools. As these minute
details have consequences of some importance, I do not hesitate to
multiply them: they all help to throw light upon the subject which we
are investigating. Let us once more see what the Longicorns are able
to tell us.

An inhabitant of old pine-stumps, _Criocephalus ferus_ makes an
exit-gallery which yawns widely on the outside world, opening either
on the section of the stump or on the sides. The road is barricaded
about two inches down with a long plug of coarse shavings. Next comes
the nymph's cylindrical, compressed apartment, which is padded with
woody fibres. It is continued underneath by the labyrinth of the
larva, the burrow crammed full of digested wood. Note also the
complete boring of the liberating passage, including the bark when
there is any.

I find _Stromatium strepens_ in ilex-logs which have been stripped of
their bark. There is the same method of deliverance, the same passage
curving gently towards the nearest outside point, the same barricade
of shavings above the cell. Was the passage also carried through the
bark? The stripped logs leave me ignorant as to this detail.

_Clytus tropicus_, a sapper of the cherry-tree, _C. arietis_ and _C.
arvicola_, sappers of the hawthorn, have a cylindrical exit-gallery,
with a sharp turn to it. The gallery is masked on the outside by a
remnant of bark or wood, hardly a millimetre thick,[2] and widens, not
far from the surface, into a nymphosis-chamber, which is divided from
the burrow by a mass of packed sawdust.

[Footnote 2: .039 inch.--_Translator's Note_.]

To continue the subject would entai