In the first fortnight of July, the male Pine-chafers observed in the vivarium withdraw to one side, sometimes bury themselves and die quite peacefully, killed by age. The mothers, on the other hand, busy themselves with laying their eggs, or, more accurately, with sowing them. They poke the soil with the tip of their abdomen, shaped like a blunt ploughshare, sinking into it sometimes altogether, sometimes to their shoulders. The eggs, to the number of a score, are laid separately, one by one, in little round cavities the size of a pea. They receive no further attention. They are positively dibbled into the ground.
This method recalls the arachis, the African[13] Leguminosa, which curls its floral peduncles and thrusts its oleaginous seeds with their nutty flavour, underground to germinate. It reminds us too of a plant of [[211]]my own country-side, the subterranean or double-fruited vetch (Vicia amphicarpos, Dorth.), which produces two sorts of pods, the first above ground, containing numerous seeds, the second under the surface, containing large seeds, usually no more than two in number. For that matter the two kinds are equal in value and give a similar yield.
Let the soil be moistened and everything is ready for the germination; the preliminary sowing has been done by the vetch and the arachis themselves. Here the plant vies with the animal in maternal cares: the Pine-chafer does no more than the two Leguminosæ. She sows in the ground and that is all, absolutely all. How far removed we are from the Minotaur, so careful of her family!
The eggs, ovoids blunted at either end, measure four to five millimetres[14] in length. They are a dull white, firm to the touch, as though supplied with a chalky shell copied from that of a Hen’s egg. This appearance is deceptive: what remains after the hatching is a delicate, flexible, translucent membrane. The chalky look is due to the contents, [[212]]which show through. The hatching takes place in the middle of August, a month after the laying.
How shall I feed the grubs and watch them take their first mouthfuls? I go by what I have learnt from the spots frequented by the grown larvæ. I make a mixture of moist sand and the fine detritus of any leaves whatever browned with decay. The new-born grubs thrive in this environment: I see them opening short galleries here and there, seizing on decayed particles and devouring them with every sign of satisfaction, so much so that, if I had the leisure to continue this rearing for the three or four years required, I should certainly obtain larvæ ripe for transformation.
But there is no need to waste my time in rearing them thus: by digging in the fields I obtain the fully developed grub. It is magnificently fat, bent into a hook, a creamy white in front and an earthy brown behind, because of the wallet in which it hoards the stercoral treasure destined later to plaster and cement the cell in which the nymphosis will take place. All these hook-shaped wallet-bearers, Oryctes- and Cetonia-larvæ, [[213]]Cockchafer- and Anoxia-grubs, are hoarders of fæcal matter: they reserve in their brown paunches the wherewithal to build themselves a lodging when the time comes.
I collect my fat grubs in a sandy soil, where lean grass-tufts grow, at a great distance from any resinous tree except the cypress, which the adult insect does not visit. The Cockchafer, therefore, after her regulation frolics on the pines, came to this place from afar to lay her eggs. She feeds frugally on pine-needles; her larva calls for the remnants of any leaves softened by underground putrefaction. This is why the nuptial paradise is deserted.
The larva of the Common Cockchafer, the White Worm, a voracious nibbler of tender roots, is the scourge of our crops; that of the Pine Cockchafer seems to me to work hardly any havoc. Decayed rootlets, decomposing vegetable remains, are all that it needs. As to the adults, they browse upon the green pine-needles, without abusing their privilege. If I were a land-owner, I should not trouble my head about their devastations. A few mouthfuls taken from the immense store of leaves, a few pine-needles robbed of their [[214]]points, are not a serious matter. Let us leave the Pine Cockchafer alone. He is an ornament of the balmy twilight, a pretty jewel of the summer solstice. [[215]]
[1] The Rhinoceros Beetle. Cf. The Glow-worm and Other Beetles: chap. xiii.—Translator’s Note. [↑]