I found these Beetles in a certain pine-woods where there are plenty of mushrooms. It is a pleasant place, where my whole family like to go in the mild days of autumn. They find everything there: old Magpies’ nests, made of bundles of twigs; Jays squabbling with each other, after filling their crops with acorns on the oaks hard by; Rabbits suddenly starting out of a rosemary bush, showing their little white upturned tails. There is lovely sand for the children to dig tunnels in, sand that is easy to build into rows of huts which we thatch with moss and top with a bit of reed by way of a chimney. And when we are there we lunch off an apple to the sound of the Æolian harps of the breezes softly sighing through the pine-needles!
Yes, for the children it is a real paradise. The grown-ups also enjoy it, and one of my chief enjoyments is watching my Truffle-beetle. His burrows may be seen here and there. The door is left open and surrounded merely by a padding of sand. The burrow is about nine inches deep, going straight down in very loose soil. When I cut into it with a knife, I often find that it is empty. The insect has left during the night, having finished its business there and gone to settle elsewhere. The Truffle-beetle is a tramp, a night-walker, who leaves his home whenever he feels like it and easily gets a new one. Sometimes I do find the insect at the bottom of the pit, always alone, sometimes a male, sometimes a female, never two at the same time. The burrow is not a house for the family; it is a sort of bachelor house, dug for comfort only for the solitary Beetle.
The Beetle in this house is clutching a small mushroom, usually partly eaten. He will not part from it. It is his treasure, his worldly goods. Scattered crumbs tell us that we have caught him feasting.
When we take his prize away from him we find that it is a sort of little underground mushroom, closely related to the truffle.
This throws a light upon the habits of the Beetle and his reason for making new burrows so often. In the calm of the twilight, the little gadabout takes to the fields, chirruping softly as he goes, cheering himself with song. He explores the soil, questions it as to its contents, just as the Dog does when hunting for truffles. His sense of smell tells him when the coveted morsel is underneath, covered by a few inches of sand. Certain of the exact spot where the thing lies, he digs straight down and never fails to reach it. As long as the provisions last, he does not go out again. Blissfully he feeds at the bottom of the well he has dug to reach the mushroom. He does not care whether his door is open or not.
When he has eaten all his food, he moves, looking for more, and to find it he digs a new burrow, which will be given up in its turn. Thus he spends all autumn and the next spring, the seasons for mushrooms, traveling from one of his little hotels to another.
This truffle which the Beetle hunts appears to have no particular odor. How, then, can he detect it from the ground over the place where it is buried? He is a clever Beetle, and we do not know yet just how he manages it.