Water, quiet, still water, affords a place of action to a very amusing little fellow (gyrinus natator), which about the month of April, if the weather be tolerably mild, we see gamboling upon the surface of the sheltered pool; and every schoolboy, who has angled for a minnow in the brook, is well acquainted with this merry swimmer in his shining black jacket. Retiring in the autumn, and reposing all the winter in the mud at the bottom of the pond, it awakens in the spring, rises to the surface, and commences its summer sports. They associate in small parties of ten or a dozen, near the bank, where some little projection forms a bay, or renders the water particularly tranquil; and here they will circle round each other without contention, each in his sphere, and with no apparent object, from morning until night, with great sprightliness and animation; and so lightly do they move on the fluid, as to form only some faint and transient circles on its surface. Very fond of society, we seldom see them alone, or, if parted by accident, they soon rejoin their busy companions. One pool commonly affords space for the amusement of several parties; yet they do not unite, or contend, but perform their cheerful circlings in separate family associations. If we interfere with their merriment they seem greatly alarmed, disperse, or dive to the bottom, where their fears shortly subside, as we soon again see our little merry friends gamboling as before. This lively little animal, arising from its winter retreat shortly after the frog, at times in March, continues its gambols all the summer long, remaining visible generally until the middle of October, thus enjoying a full seven months of being; a long period of existence for insects, which are creatures subject to so many contingencies, that their lives appear to be commonly but brief, and the race continued by successive productions. All these water creatures must be endowed with much perception. Cold as this element is in early spring, when the ice of winter is hardly dissolved, and the fluid only 6 or 7 degrees above freezing, yet they become immediately sensible of this temperature, and are excited to animation and the vocations of their being. I have never observed the larvæ of this creature in any state. When they retire in the autumn, these insects appear of a uniform size, and emerging in the spring they are all apparently full grown, and during the summer none of smaller dimensions associate with the family parties. This plain, tiny, gliding water-flea seems a very unlikely creature to arrest our young attentions; but the boy with his angle has not often much to engage his notice; and the social, active parties of this nimble swimmer, presenting themselves at these periods of vacancy, become insensibly familiar to his sight, and by many of us are not observed in after life without recalling former hours, scenes of perhaps less anxious days: for