Life everywhere! The air is crowded with birds--beautiful, tender, intelligent birds, to whom life is a song and a thrilling anxiety, the anxiety of love. The air is swarming with insects--those little animated miracles. The waters are peopled with innumerable forms, from the animalcule, so small that one hundred and fifty millions of them would not weigh a grain, to the whale, so large that it seems an island as it sleeps upon the waves. The bed of the seas is alive with polypes, crabs, star-fishes, and with sand-numerous shell-animalcules. The rugged face of rocks is scarred by the silent boring of soft creatures; and blackened with countless mussels, barnacles, and limpets. Life everywhere! on the earth, in the earth, crawling, creeping, burrowing, boring, leaping, running. If the sequestered coolness of the wood tempt us to saunter into its chequered shade, we are saluted by the murmurous din of insects, the twitter of birds, the scrambling of squirrels, the startled rush of unseen beasts, all telling how populous is this seeming solitude. If we pause before a tree, or shrub, or plant, our cursory and half-abstracted glance detects a colony of various inhabitants. We pluck a flower, and in its bosom we see many a charming insect busy at its appointed labour. We pick up a fallen leaf, and if nothing is visible on it, there is probably the trace of an insect larva hidden in its tissue, and awaiting there development. The drop of dew upon this leaf will probably contain its animals, visible under the microscope. This same microscope reveals that the _blood-rain_ suddenly appearing on bread, and awakening superstitious terrors, is nothing but a collection of minute animals (_Monas prodigiosa_); and that the vast tracts of snow which are reddened in a single night, owe their colour to the marvellous rapidity in reproduction of a minute plant (_Protococcus nivalis_). The very mould which covers our cheese, our bread, our jam, or our ink, and disfigures our damp walls; is nothing but a collection of plants. The many-coloured fire which sparkles on the surface of a summer sea at night, as the vessel ploughs her way, or which drips from the oars in lines of jewelled light, is produced by millions of minute animals.