PLATE V

And then how original are their frontal decorations! These peace-lovers delight in the panoply of war, as though they, the inoffensive ones, thirsted for battle. Many of them crown their heads with threatening horns. Let us mention that horned one whose story will occupy us more particularly. I mean Onthophagus [[81]]Taurus, clad in raven black. He wears a pair of long horns, gracefully curved and branching to either side. No pedigree bull, in the Swiss meadows, can match them for curve or elegance.

The Onthophagus is a very indifferent artist: his 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. Onthophagus Taurus 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 laboratory.

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 prototype from 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 against the walls of the jar, especially against the bottom wall. When the support is vertical, the sack is a short cylinder divided lengthwise, with a 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 undefined oval pastille, flat at the bottom, bulging and vaulted at the top. To the general inaccuracy of these contorted shapes, ruled by no very definite pattern, we must add the coarseness of the surfaces, all of which, with the [[82]]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 middling depth. Here, working with the shield, the chine and the fore-legs, which are toothed like a rake, he forces back and heaps around him the materials which he has moved, so as to obtain as best he 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 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 flint 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 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 contrived at the bottom: the hatching-chamber, on whose inner wall the egg is laid. Next comes the gathering of the provisions intended for the worm, a gathering made with nice precautions. Lately, 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 contrived with a punch. When trying a cheese, the buyer employs a hollow cylindrical taster, which he [[83]]drives well in and pulls 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. Finally, a plug of the same mortar, the sides of which are made partly of sand and partly of stercoral cement, roughly closes the cell, in such a way that an outward inspection does not allow one to distinguish front from back.

To judge 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 content, the egg fixed on the wall, sometimes at the bottom of the cell and sometimes on the side. The egg is a tiny white cylinder, rounded at either end and measuring a millimetre[1] 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 hind-end and projects into space.