The Sacred Beetle, and Others

by Jean-Henri Fabre

She is small, I agree; but littleness does not diminish talent in the least, as witness the Titmouse, with his pendulous nest, the Wren and the Canary, who, although among the smallest of our little birds, are incomparable artists. The near kinswomen of the Onthophagus excel in making beautiful ovoids and pear-shaped gourds. She herself, so tiny and so precise, ought to do even better.

Well, the table deceives us, the formula lies: the Onthophagus is a very indifferent artist; her nest is a rudimentary piece of work, hardly fit to be acknowledged. I obtain it in profusion from the six species which I have brought up in my jars and flower-pots. The Bull Onthophagus alone provides me with nearly a hundred; and I find no two precisely alike, as pieces should be that come from the same mould and the same workshop. [[271]]

To this lack of exact similarity, we must add inaccuracy of shape, now more now less accentuated. It is easy, however, to recognize among the bulk the pattern upon which the clumsy nest-builder works. It is a sack shaped like a thimble and standing erect, with the spherical thimble-end at the bottom and the circular opening at the top.

Sometimes the insect establishes itself in the central region of my apparatus, in the heart of the earthy mass; then, the resistance being the same in every direction, the sack-like shape is pretty accurate. But, generally, the Onthophagus prefers a solid basis to a dusty support and builds on the walls of the jar, especially on the bottom. When the support is vertical, the sack is a longitudinal section of a short cylinder, with the smooth flat surface against the glass and a rugged convexity every elsewhere. If the support be horizontal, as is most frequently the case, the cabin is a sort of undecided oval lozenge, flat at the bottom, bulging and vaulted at the top. To the general inaccuracy of these contorted shapes, regulated by no very definite pattern, we must add the coarseness of the surfaces, all of which, with the exception of the parts touching the glass, are covered with a crust of sand.

The manner of procedure explains this uncouth exterior. As laying-time draws nigh, the Onthophagus bores a cylindrical pit and descends underground to a moderate depth. Here, working with her forehead, her chin and her fore-legs, which are toothed like a rake, she forces back and heaps around her the materials which she has moved, so as to obtain as best she may a nest of suitable size.

The next thing is to cement the crumbling walls of the cavity. The insect climbs back to the surface by [[272]]way of its pit; it gathers on its threshold an armful of mortar taken from the cake whereunder it has elected to set up house; it goes down again with its burden, which it spreads and presses upon the sandy wall. Thus it produces a concrete casing, the gravel of which is supplied by the wall itself and the cement by the produce of the Sheep. After a few trips and repeated strokes of the trowel, the pit is plastered on every side; the walls, encrusted all over with grains of sand, are no longer liable to give way.

The cabin is ready: it now wants only a tenant and stores. First, a large free space is made at the bottom: the hatching-chamber, where the egg is laid on the wall. Next comes the collecting of the provisions intended for the grub, a collecting done with scrupulous care. Recently, when building, the insect worked upon the outside of the doughy mass and took no notice of the earthy blemishes. Now, it penetrates to the very centre of the lump, through a gallery that looks as though it were made with a punch. When trying a cheese, the buyer employs a scoop, the hollow, cylindrical taster which is driven well in and pulled out with a sample taken from the middle of the cheese. The Onthophagus, when collecting for her grub, goes to work as though equipped with one of these tasters. She bores an exactly round hole into the piece which she is exploiting; she goes straight to the middle, where the material, not being exposed to the contact of the air, has kept more savoury and pliable. Here and here alone are gathered the armfuls which, gradually stowed away, kneaded and heaped up to the requisite extent, fill the sack to the top. Lastly, a plug of the same mortar, the sides of which are made partly of sand and partly of stercoral cement, [[273]]roughly closes the cell, in such a way that an external inspection does not allow one to distinguish front from back.

To judge of the work and its merit, we must open it. A large empty space, oval in shape, occupies the rear end. This is the birth-chamber, huge in dimensions compared with its contents, the egg fixed on the wall, sometimes at the bottom of the cell and sometimes on the side. This egg is a tiny white cylinder, rounded at each tip and measuring a millimetre[6] in length immediately after it is laid. With no other support than the spot on which the oviduct has planted it, it stands on its hinder end and projects into space.

A more or less enquiring glance is quite surprised to find so small a germ contained in so large a box. What does the tiny egg want with all that room? When carefully examined within, the walls of the chamber suggest another question. They are coated with a fine greenish pap, semifluid and shiny, the appearance of which does not agree with either the external or the internal aspect of the lump from which the insect has extracted its materials. A similar lime-wash is observed in the nest which the Scarab, the Copris, the Sisyphus, the Geotrupes and other makers of stercoraceous preserves contrive in the very heart of the provisions, to receive the egg; but nowhere have I seen it so plentiful, in proportion, as in the hatching-chamber of the Onthophagus. Long puzzled by this brothy wash, of which the Sacred Beetle provided me with the first instance, I at one time took the thing for a layer of moisture oozing from the bulk of the victuals and collecting on the surface of the enclosure without other effort than capillary action. That was the interpretation [[274]]of this varnish which I accepted in various earlier passages.

I was wrong. The truth is something much more remarkable. To-day, better informed by the Onthophagus, I reopen the question: is this lime-wash, this semifluid cream, the result of a natural oozing, or is it the product of maternal foresight? A simple and conclusive experiment will give us the answer. I ought to have made it at the outset. I did not think of it, because the simple is usually the last thing that we call to our aid. Here is the experiment.