twilight the little truffle-hunter goes abroad, chirping softly to
encourage itself. It explores the soil, and interrogates it as to its
contents, exactly as does the truffle-gatherer's dog. The sense of smell
warns it that the desired object is beneath it, covered by a few inches
of sand. Certain of the precise point where the treasure lies, it sinks
a well vertically downwards, and infallibly reaches it. So long as there
is food left it does not again leave the burrow. It feasts happily at
the bottom of its well, heedless of the open or imperfectly closed
burrow.

When no more food is left it removes in search of further booty, which
becomes the occasion of another burrow, this too in its turn to be
abandoned. So many truffles eaten necessitate so many burrows, which are
mere dining-rooms or pilgrim's larders. Thus pass the autumn and the
spring, the seasons of the _Hydnocystis_, in the pleasures of the table
and removal from one house to another.

To study the insect _rabassier_ in my own house I had to obtain a small
store of its favourite food. To seek it myself, by digging at random,
would have resulted merely in waste of time; the little cryptogam is not
so common that I could hope to find it without a guide. The
truffle-hunter must have his dog; my guide should be the Bolboceras
itself. Behold me, then, a _rabassier_ of a kind hitherto unknown. I
have told my secret, although I fear my original teacher will laugh at
me if he ever hears of my singular form of competition.

The subterranean fungi grow only at certain points, but they are often
found in groups. Now, the beetle has passed this way; with its subtle
sense of smell it has recognised the ground as favourable; for its
burrows are numerous. Let us dig, then, in the neighbourhood of these
holes. The sign is reliable; in a few hours, thanks to the signs of the
Bolboceras, I obtain a handful of specimens of the _Hydnocystis_. It is
the first time I have ever found this fungus in the ground. Let us now
capture the insect--an easy matter, for we have only to excavate the
burrows.

The same evening I begin my experiments. A wide earthen pan is filled
with fresh sand which has been passed through a sieve. With the aid of a
stick the thickness of a finger I make six vertical holes in the sand:
they are conveniently far apart, and are eight inches in depth. A
_Hydnocystis_ is placed at the bottom of each; a fine straw is then
inserted, to show me the precise