2.—THE SEXTONS AT WORK: BURYING THE BODY.
As a rule, when a carcass appears, a pair of burying beetles of the same species—a husband and wife—fly up to the scene of operations together and take possession of the prey; though in the illustration Mr. Enock has represented several kinds engaged at once in staking out claims, which indeed happens often enough in nature. But if you count the number on any one dead bird or animal, you will almost always find they are even in number—in other words, so many pairs, male and female. No. 2 shows us the next act in the funeral drama. The male beetles, after satisfying their own immediate hunger, proceed to bury the carcass in a very curious and laborious manner. You would wonder how so small a creature could produce so great a result: the fact is, the beetles attain their end by continuous under-cutting. The female hides herself in the body: the male buries her alive and the dead creature with her. He first drags the mouse, frog, or bird to a suitable spot where the soil is soft enough to admit of excavation; and sometimes three or four males have to combine for this purpose. They then proceed to dig with their heads, which are tools specialized for the purpose, and provided with strong and powerful muscles. The antennæ have also assumed for this object a short club-shaped type, very suitable for a navvy's mattock. The little engineers begin by excavating a furrow all round the body, and then a second inside that again, throwing the earth out of each into the previous one: and so on till the carcass begins to sink into the hollow. They then dig and tunnel beneath it, carrying out loads of earth, one after another, till bit by bit the carcass collapses into the hole, first in front, then behind, and has reached a level considerably below the surface. Then they throw in the earth they have excavated, and cover up the body with the females inside it; after which, I regret to say, they proceed to hold a very cannibalistic funeral service above it. The funeral service consists in eating as much of the body as they desire for their own purposes: when they have satisfied their appetite, they begin to think of the interests of posterity. The mother beetle proceeds to lay her tale of eggs in the decently-buried body, for every animal knows by instinct the precise place in which to deposit its young and the precise food which happens to suit them.
After the eggs are laid, the two parent beetles crawl out of the hole and cover it carefully up so as to conceal the hiding-place. So far as they themselves are concerned, their only object in all this is to procure food for themselves and their infant young. But the wider effects of such scavenger insects go very far. For we now know that there is no disinfectant so good as the top layer of the soil, which is not really mere dead earth (as most people imagine), but a mingled mass of ramifying life—a little foundation of clay and sand intermixed with endless minute organisms, both animal and vegetable—fungi, bacteria, mites, weevils, and all sorts of petty creatures, which eat up and destroy harmlessly all dead matter subjected to their influence. The earth is thus a most admirable deodorizer and purifier: and burial in its top layers, the body being freely exposed to the rapid action of the devouring microbes, is a most sanitary mode of disposing of refuse. Thus the part that is played in the East by vultures and jackals, or by the wild dogs of Constantinople, is far more effectually and unobtrusively played in our fields and meadows by the many kinds of burying beetles and other insect scavengers. If we remember how great a nuisance a single dead rat becomes in a house, we can faintly picture to ourselves the debt we owe to these excellent and unnoticed little sanitary commissioners. Without them, our fields would not smell so fresh, nor would our flowers bloom so bright; for we must remember that by burying the dead beasts they are not only preventing disease but also manuring the pastures in the best possible fashion. The bones of small animals decay rapidly and make excellent material for the growth of vegetation. The beetles as a rule hunt by night only, and find their prey, as vultures do, by the sense of smell. When they first find it, the male hovers above it like an eagle, circling round and round, so as to point it out to his mate; the female flies straight to it, and buries herself without delay in the rich banquet.
But what becomes at last of the buried bodies? No. 3 will show you. The female beetle lays in each body about as many eggs as she thinks it will support. In a very short time the eggs hatch out, and the grubs begin to devour the abundant feast provided for them. The two grubs to the right in the illustration are the young of our friend the orange-banded burying beetle: the one to the left is a larva of an allied form known by the poetical name of Silpha. They set to work at once on the remains of the mouse, and thoroughly strip the bones of every fibre of flesh. As soon as the skeleton is bare, they consider it time to leave off feeding, and pass on to the second stage of their existence—the pupa, or mummy-case.
3.—THE GRUBS UNDERGROUND; FEEDING UPON THE BODY.
As larvæ, the young burying beetles look like worms, and have six short legs. No. 4 shows them in the intermediate stage, when they have retired into a clay cell, or cocoon, and are undergoing their transformation into the perfect insect. We are here supposed to have removed the soil on one side so as to give a view into the concreted earthen chambers where the pupæ are changing into full-grown beetles. You can see the much longer legs of the adult insect beginning to develop, while the head assumes slowly its later form. The grubs remain in the cocoon through the winter, and emerge in spring as winged beetles, when they fly away with their brilliant wing-cases raised, in search of congenial mates and more dead field-mice. The best places to look for all these beetles are the "keeper's trees," on which game-keepers hang up the jays and weasels they shoot, to encourage the others. If you tap one such dead weasel you will generally find it is simply swarming with insect life.
4.—NO MORE LEFT! THE GRUBS IN THEIR COCOONS TURNING INTO BEETLES.
Yet, strange to say, even the insect undertakers themselves are not without their ideas of beauty and their musical perceptions. The orange bands of our commonest English kind have been developed as attractions for their admiring mates; and the male beetles have also a musical instrument of their own in the shape of a peculiar rasp-like ring on the body, which they can rub against the wing-cases, and so produce a much-appreciated chirping. Such instrumental music is always employed, like the song of birds, as a charm to heighten the attractiveness of the suitor: and male burying beetles may be heard on the evenings of sunny days competing with one another in musical contests. Indeed, it often happens that animals which seem to us disgusting or unclean display among themselves much æsthetic taste, and are gifted with more sense of beauty or love of music than many other forms where our human eyes would be more inclined to look for the presence of these higher endowments.