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.