Another of the ravenous creatures that infest our pools is the great water-beetle (ditiscus marginalis); and perhaps it is the most ferocious of any of them, being adapted by every provision for a life of rapine, endued with great muscular power, armed with a thick and horny case over its body, and having its eyes large to observe all the creatures about it, and powerful mandibles to seize and reduce them to fragments. It riots on the polyphemus of the pool; and having thinned its herd in one place, is supplied with wings to effect a removal to a fold better furnished. It even eats the young of the frog; and its bite is so powerful, as to be painfully felt by the hand that holds it a captive, though defended by a glove. In the larvæ state it is almost equally destructive; it swims admirably; its hinder legs are long and brawny, beside being aided by a fringe of hairs, so that they are powerful oars to propel its body with celerity and ease. Nor must we omit a peculiarity attending the constitution of this beetle, which marks it as a creature especially endowed for the station in which it is placed. Multitudes of insects exist in the larva state for a certain space of time in water, and, having accomplished a given period in this state perfecting their forms, they take wings and become aërial creatures, after which a return to the element whence they sprang would be death to them. But this beetle, when it has passed from the larva state and obtained its wings, still lives in that water which nourished it to this state of perfection, without any inconvenience, as long as it suits its inclination; when weary of this place, or its food becoming scarce, it wings its way to another pool, into which it immediately plunges, and recommences its life of rapine. Having deposited its eggs in autumn, we suppose it to die in the winter; yet many may survive this season, and, arising from the mud in the spring, be undistinguished from the recently perfected larvæ. Such little notices and indications of the habits of these obscure creatures, though certainly unimportant, are not perhaps wholly unprofitable; for we so darkly see our way, and proceed so slowly in acquiring intelligence of the paths of nature, that nothing should be considered as beneath regard that we meet with in them, and every advancing step must elevate the mind, as it affords additional knowledge of the solicitude and provision of the great Architect of creation in the appointment and endowment of his creatures; since, though we are very rarely able to comprehend even the object of existence, we see sufficient to convince us, that such care and such powers were not bestowed except for some wise and good purpose. It seems hardly possible that mankind can ever obtain anything approaching to the comprehension of the motives of Providence, because they have not, as far as is apparent to us, individual and separate bearings, but are connecting and