The Fly has deserved well of hygiene. The first to come to the dead Mole, she left behind her a garrison of scavengers which, without dissecting-instruments, whether lancets or scalpels, set to work upon the corpse. The most urgent matter was to sterilize the carcase, to extract from it such substances as are readily corrupted, the source of rapid and dangerous putrescence. And this is what the maggot has been doing. From its pointed mouth, for ever poking and rummaging, it dribbled forth a solvent as effective as any in my laboratory; with this reagent it dissolved the flesh and viscera, or at least reduced them to a thick liquid broth. Gradually the soil is saturated with the fertilizing moisture, which the plant will soon restore to the laboratory of living chemistry. When her mission is completed, the Fly herself becomes a danger, because of her excessive numbers. In order to perform their pressing task more quickly, the maggots operate in legions. If not checked, they would encumber the world. The balance of things in general demands their disappearance. Then, in due season, the exterminator arrives, the Saprinus doting on fat sausages, the slow-trotting Beetle in black armour who massacres the vermin and leaves only enough survivors to maintain the race. The Mole is now a dried-up mummy, but is harmful if affected by moisture. This remnant also has to disappear. The Dermestes is entrusted with the task. She establishes herself beneath the remains in company with the Silpha, her collaborator. With her patient tooth she files, rasps and disarticulates as long as a scrap of cartilage is left to gnaw. She is greatly assisted by her starveling larvæ, who are lither in the back and therefore able to slip into narrow crevices. By the time the Dermestes has finished, my pans contain so many heaps of bones, a conglomeration of Snakes’ vertebræ arranged in a row, Moles’ jaws, with their fine, insectivorous teeth, Frogs’ toe-and-finger-joints, radiating like knotty sticks, Rabbits’ skulls overlapping their powerful incisors, all white and clean enough to arouse the envy of the people who prepare our anatomical specimens. Yes, working one on the soft parts and then the other on the hard, the maggot and the Dermestes have performed a meritorious task. There is no longer any pestilential filth, any dangerous effluvia. The residue, mostly of a chalky nature, if it still offends the eye, is at least capable of vitiating the air, the first aliment of life. General hygiene is satisfied. Besides his bones, the Mole has left the tatters of his fur; the Snake has been flayed in tatters like the skin which boiling water strips from a fleshy root. The Fly’s solvent was powerless to affect these refractory substances; the Dermestes refused them. Will these epidermic shreds remain unutilized? Certainly not. Nature, the sublime economist, takes good care that all things return to the treasury of her works. Not an atom must be allowed to go astray.