The Sacred Beetle, and Others

by Jean-Henri Fabre

When the weather is severe, what becomes of the larva in the retreat which it has succeeded in making at the far end of its box? The exceptional cold of January and February 1895 will answer this question. My cages, always left in the open air, had repeatedly undergone a drop in temperature of some ten degrees below freezing-point. In this arctic weather, I conceived a wish to go in search of information and learn how things were progressing in my unprotected cages.

I could not manage it. The bed of earth, wetted by the earlier rains, had become a compact block throughout, which I should have had to break up like a stone with a hammer and chisel. Extraction by violent means was [[228]]not practicable: I should have endangered everything with my hammering. On the other hand, if any life remained in the frozen mass, I should have placed it in jeopardy by changing the temperature too suddenly. It was better to await the very slow natural thaw.

Early in March I inspect the cages again. This time there is no ice left. The earth is yielding and easy to dig. All the adult Geotrupes have died, bequeathing me a fresh supply of sausages, almost as plentiful as that which I had gathered and placed in safety in October. They have all perished; there is not a single survivor. Is cold or old age to blame?

At this very time and later, in April and May, when the new generation is wholly in the larval or at most in the nymphal stage, I often find adult Geotrupes busy in their scavenging-works. The old ones therefore see a second spring; they live long enough to know their children and to work with them, as do the Scarabæi, the Copres and others. These early ones are veterans. They have escaped the hardships of winter because they have been able to bury themselves far enough underground. Mine, kept captive between a few boards, have died for want of a sufficiently deep pit. At a time when they needed three feet of earth to shelter themselves, they had less than twelve inches. It was cold, therefore, that killed them, rather than age.

The low temperature, while fatal to the adult, has spared the larva. The few sausages left in position after my October diggings contain the grub in excellent condition. The protecting sheath has fulfilled its office to perfection: it has preserved the sons from the catastrophe that caused the death of the parents. [[229]]

The other cylinders, fashioned in the course of November, contain something even more remarkable. In their hatching-chamber, at the bottom, they hold an egg, all plump and shiny and as healthy-looking as though it had been laid that day. Can life still exist there? Is it possible, after the best part of the winter has been passed in a block of ice? I dare not believe it. The sausage itself has not an attractive appearance. It is darkened by fermentation, smells musty and does not suggest food worth having.

At all events, I will take the precaution of bottling the miserable puddings, after ascertaining that the egg is there in each case. I was well-advised. The fresh aspect of the germs, after wintering under such rude conditions, did not belie them. The hatching was soon effected; and early in May the late arrivals were almost as well-developed as their seniors, hatched in the autumn.

Some interesting facts are revealed by this piece of observation. First of all, the laying-period of the Geotrupes is a fairly long one, lasting from September to some time in November. At that date the first hoar-frosts begin; the soil is not warm enough to hatch the eggs; and the last ones, unable to hatch as swiftly as their predecessors, wait for the return of the fine weather. A few mild April days are enough to reawaken their suspended vitality. Then the usual evolution goes on, and this so rapidly that, notwithstanding a delay of five or six months, the backward larvæ are very nearly as big as the others by May, when the first nymphs appear.

Secondly, the Geotrupes’ eggs are capable of enduring the trials of severe cold unscathed. I do not know the exact temperature inside the frozen block which I tried to tackle with a mason’s chisel. Outside, the thermometer [[230]]sometimes fell to ten degrees below freezing-point; and, as the cold period lasted a long time, we may believe that the layer of earth in my boxes was equally cold. Now the Geotrupes’ puddings were enclosed in that frozen mass turned to a block of stone. A generous allowance must no doubt be made for the non-conductivity of these puddings composed of thready materials; the wall of dung did, to a certain extent, protect the larva and the egg against the biting cold, which, if experienced direct, would have been fatal. No matter: in that atmosphere the dung-cylinders, damp at the start, must in the long run have acquired the hardness of stone. In their hatching-chamber, in the tunnel made by the larva, the temperature undoubtedly sank below freezing-point.

Then what became of the grub and the egg? Were they really frozen? Everything seems to tell us so. That this most delicate of all delicate things, a germ, a rudiment of life in a blob of glair, should harden, turn into a bit of stone and then resume its vitality and continue its evolution after thawing seems inadmissible. And yet circumstances confirm it. We should have to credit the Geotrupes’ sausages with athermanous properties unequalled by any other substance to regard them as a sufficient protection against such intense and lasting refrigeration. What a pity that we could derive no information from the thermometer in this instance! After all, if complete freezing is unproven, one point has been established for certain: the egg and the grub of the Geotrupes can support and survive very low temperatures in their protecting sheath.