For the rest, we are far from saying, as the author referred to makes us say, that the bird is the sole purifier of creation. One must be blind, and indeed senseless, not to see that he shares this mission with the insect. The action, too, of the latter is undoubtedly more efficacious in the pursuit of a world of living atoms, which the insect, whose eyes are microscopes, detects and pounces upon in numerous obscure corners, inaccessible to the bird. The bird, on the other hand, is the essential purifier of everything demanding long-sightedness and the power of flight,--as, for example, the frightful clouds of invisible animalcules which float and swim in the air, and therefore pass into our lungs. As a rule, the equilibrium of species is desirable. All are more or less useful. We willingly join with the author of the paper referred to in the wish that those insects which prey upon the smaller species might be specially distinguished and spared. The peasant destroys them indiscriminately, without knowing that by killing, for instance, the dragon-fly (or _libellula_)--the brilliant murderess which slays a thousand insects daily--he is helping the latter: becomes the auxiliary of the insects, the preserver and propagator of the enemies which devour his substance. The terrible cicindela does not fly so high, but with its crossed daggers, or rather the two scimitars which serve it for jaws, accomplishes a swift and almost incredible havoc among the smaller insects. Take care, then, and respect it. Do not listen to the child who is dazzled by the beauty of its wings, nor, to please him, impale on the needle-point your admirable insect-hunter, the efficacious auxiliary of the agriculturist! [Illustration] The carabi,--immense warrior-tribes armed to the very teeth, and displaying an ardent activity beneath their heavy coats of mail,--are the true guardians of your fields; and day and night, without holiday or repose, protect your crops. They themselves never touch the smallest blade or seed. Their sole occupation is to capture thieves, and they ask for no other reward than the thieves' bodies. Others toil underground. The innocent lobworm, which pierces and stirs up the soil, gets ready in a marvellously excellent manner the muddy and clayey earths which are deficient in evaporation. Others, in company with the mole, hunt far down in the depths the cruel enemy of agriculture, the horribly voracious larva of the destructive cockchafer, which, for three years, has been preying on the roots beneath the surface. The insectivorous insects put forth undeniable claims to the protection of man, whose allies they are. But even among the herbivora there are useful destroyers of harmful plants. The useless, pungent, and in every sense disagreeable nettle, which scarcely a single quadruped will deign to touch, fifty species of insects, in fellowship with ourselves, labour to destroy. * * * * *