is of great importance to man, merely with relation to his own comfort and security. The injuries which they inflict upon us are extensive and complicated; and the remedies which we attempt, by the destruction of those creatures, both insects, birds, and quadrupeds, who keep the ravagers in check, are generally aggravations of the evil, because they are directed by an ignorance of the economy of nature. The little knowledge which we have of the modes by which insects may be impeded in their destruction of much that is valuable to us, has probably proceeded from our contempt of their individual insignificance. The security of property has ceased to be endangered by quadrupeds of prey, and yet our gardens are ravaged by aphides and caterpillars. It is somewhat startling to affirm that the condition of the human race is seriously injured by these petty annoyances; but it is perfectly true that the art and industry of man have not yet been able to overcome the collective force, the individual perseverance, and the complicated machinery of destruction which insects employ. A small ant, according to a most careful and philosophical observer, opposes almost invincible obstacles to the progress of civilization in many parts of the equinoctial zone. These animals devour paper and parchment; they destroy every book and manu script. Many provinces of Spanish America cannot, in consequence, shew a written document of a hundred years' existence. "What development," he adds, can the civilization of a people assume, if there be nothing to connect the present with the past- if the depositories of human knowledge must be constantly renewed-if the monuments of genius and wisdom cannot be transmitted to posterity *?" Again, there are beetles which deposit their larvæ

66

*Humboldt, Voyage, lib. vii., ch. 20.

in trees, in such formidable numbers, that whole forests perish, beyond the power of remedy. The pines of the Hartz have thus been destroyed to an enormous extent; and in North America, at one place in South Carolina, at least ninety trees in every hundred, upon a tract of two thousand acres, were swept away by a small, black, winged bug. And yet, according to Wilson, the historian of American birds, the people of the United States were in the habit of destroying the red-headed woodpecker, the great enemy of these insects, because he occasionally spoilt an apple *. The same delightful writer, and true naturalist, speaking of the labours of the ivory-billed woodpecker, says, "would it be believed that the larvæ of an insect, or fly, no larger than a grain of rice, should silently, and in one season, destroy some thousand acres of pine trees, many of them from two to three feet in diameter, and a hundred and fifty feet high? In some places the whole woods, as far as you can see around you, are dead, stripped of the bark, their wintry-looking arms and bare trunks bleaching in the sun, and tumbling in ruins before every blast +." The subterraneous larva of a species of beetle (Zabrus gibbus) has often caused a complete failure of the seed-corn, as in the district of Halle in 1812. The corn-weevil, which extracts the flour from grain, leaving the husk behind, will destroy the contents of the largest storehouses in a very short period. The wire-worm and the turnip-fly are dreaded by every farmer. The ravages of the locust are too well known not to be at once recollected, as an example of the formidable collective power of the insect race. The white ants of tropical countries sweep away whole villages, with as much certainty as a fire or an inundation; and ships even have been destroyed by these

Amer. Ornith., i., p. 144. + lb., iii., p. 21. + Blumenbach.

indefatigable republics. Our own docks and embankments have been threatened by such minute ravagers.

The enormous injuries which insects cause to man may thus be held as one reason for ceasing to consider the study of them as an insignificant pursuit; for a knowledge of their structure, their food, their enemies, and their general habits, may lead, as it often has led, to the means of guarding against their injuries. At the same time we derive from them both direct and indirect benefits. The honey of the bee, the dye of the cochineal, and the web of the silk-worm, the advantages of which are obvious, may well be balanced against the destructive propensities of insects which are offensive to man. But a philosophical study of natural history will teach us, that the direct benefits which insects confer upon us are even less important than their general uses in maintaining the economy of the world. The mischiefs which result to us from the rapid increase and the activity of insects, are merely results of the very principle by which they confer upon us numberless indirect advantages. Forests are swept away by minute flies; but the same agencies relieve us from that extreme abundance of vegetable matter, which would render the earth uninhabitable, were this excess not periodically destroyed. In hot countries, the great business of removing corrupt auimal matter, which the vulture and the hyæna imperfectly perform, is effected with certainty and speed by the myriads of insects that spring from the eggs deposited in every carcass, by some fly seeking therein the means of life for her progeny. Destruction and reproduction, the great laws of Nature, are carried on very greatly through the instrumentality of insects; and the same principle regulates even the increase of particular species

of insects themselves. When aphides are so abun dant that we know not how to escape their ravages, flocks of lady-birds instantly cover our fields and gardens to destroy them. Such considerations as these are thrown out to shew that the subject of insects has a great philosophical importance--and what portion of the works of Nature has not? The habits of all God's creatures, whether they are noxious, or harmless, or beneficial, are worthy objects of our study. If they affect ourselves, in our health or our possessions, whether for good or for evil, an additional impulse is naturally given to our desire to attain a knowledge of their properties. Such studies form one of the most interesting occupations which can engage a rational and inquisitive mind; and, perhaps, none of the employments of human life are more dignified than the investigation and survey of the workings and the ways of Nature in the minutest of her productions.

The exercise of that habit of observation which can alone make a naturalist-" an out-of-door naturalist," as Daines Barrington called himself-is well calculated to strengthen even the most practical and merely useful powers of the mind. One of the most valuable mental acquirements is the power of discriminating among things which differ in many minute points, but whose general similarity of appearance usually deceives the common observer into a belief of their identity. Entomology, in this point of view, is a study peculiarly adapted for youth. According to our experience, it is exceedingly difficult for persons arrived at manhood to acquire this power of discrimination; but in early life, a little care on the part of the parent or teacher will render it comparatively easy. In this study the knowledge of things should go along with that of words. "If names perish," says

Linnæus, "the knowledge of things perishes also *." and without names, how can any one communicate to another the knowledge he has acquired relative to any particular fact, either of physiology, habit, utility, or locality? On the other hand, mere catalogue learning is as much to be rejected as the loose generalizations of the despisers of classification and nomenclature. To name a plant, or an insect, or a bird, or a quadruped rightly, is one step towards an accurate knowledge of it; but it is not the knowledge itself. It is the means, and not the end, in natural history, as in every other science.

If the bias of opening curiosity be properly directed, there is not any branch of natural history so fascinating to youth as the study of insects. It is, indeed, a common practice in many families, to teach children, from the earliest infancy, to treat the greater number of insects as if they were venomous and dangerous, and, of course, meriting to be destroyed, or, at least, avoided with horror. Associations are by this means linked with the very appearance of insects, which become gradually more inveterate with advancing years; provided, as most frequently happens, the same system be persisted in, of avoiding or destroying almost every insect which is unlucky enough to attract observation. How much rational amusement and innocent pleasure is thus thoughtlessly lost; and how many disagreeable feelings are thus created, in the most absurd manner! "In order to shew," says a writer in the Magazine of Natural History, "that the study, or (if the word be disliked) the observation of insects is peculiarly fascinating to children, even in their early infancy, we may refer to what we have seen in the family of a friend, who is partial to this, as well as to all the

* Nomina si pereant, perit et cognitio rerum.