[ocr errors]

whose usefulness is apparent to every watchful investigator; but there can be no doubt, that it is in those instances chiefly where their usefulness manifests itself by conferring some direct benefit on man, that the use of certain species becomes most apparent. Of one thing we may assure ourselves, not a single insect has been created in vain, and if we fail to discover the direct use of hundreds of these tiny atoms, we may rest satisfied that every one of them plays a more or less important part in the system of nature ; but that man will ever discover the key whereby he will be able, as it were, to unlock the record in which he will discern the Divine intention in the creation of all these infinite multitudes of living things, may very reasonably be doubted ; this is not, perhaps, a knowledge to which, in this world, he can ever attain. It would be, indeed, a glorious day for science, could we so intimately understand the nature and the intention of all created things, as to read their histories, elucidate their economies, and point out the uses of each ; but alas ! we are as yet probably not even in the right road that leads to the great temple, in the adytum of which the book of nature is to be found; and that book can only be read by those who have learnt the alphabet of the words therein inscribed : species are the letters, and at a very moderate computation these are hundreds of thousands in number.

In order to comprehend the use of the tribe of insects, it will not be time unprofitably employed if we go at once to their creation ; when we do so, we read that “on the sixth day the earth brought forth the living creature after its kind, cattle and creeping thing after their kind :" by this I understand that insects were created during the sixth day; the “grass and herb yielding seed" had been created, so that

” the waters were tenanted by fish, and the air by all manner of fowl ; so that, as the record informs us, man, cattle after their kind, the beasts of the earth, and the creeping things, appeared at a time when a preparation for their sustenance had already been made ; and in this we see at once the general law of one portion of created things being dependent upon the other. If we take a hasty glance at the habits of the several orders of insects, we shall perhaps better understand this law, in so far as regards insects. The tribe of beetles we find divided into sections, one dependent for its existence upon vegetable productions; another tribe is carnivorous, and subsists upon other divisions of its own kind ; a most extensive tribe subsists entirely upon the bodies of the higher animals ; upon some in a living state, but principally upon their bodies after death : the latter is one of those regula



tions of infinite wisdom that is most thoroughly appreciated in tropical countries, where insect life teems in incalculable profusion, and where the carcase of a dead animal requires to be quickly removed, so rapidly does decomposition ensue. Of the vegetable-feeding orders, none exceed the Orthoptera, which includes the locusts and grasshoppers. Now we cannot doubt the use of this vast order of insects; and although man frequently suffers immense loss through their visitation, yet their mission is clearly to check the superabundance of vegetation, the decomposition of which would otherwise render some districts unfitted for the residence of man.

The Lepidoptera is an order that also subsists almost entirely upon, vegetable products. The caterpillars of moths and butterflies no doubt assist in the work I have just alluded to.

The next order to which I shall refer is the Diptera—that is, the two-winged flies. Now these, again, must be regarded sectionally; one large division are, like a host of the beetles, scavengers of the earth, feeding entirely, in their grub state, upon putrid substances; others, doubtless, attack both man and beast; but man is not left to be helplessly tormented by them; he has appliances whereby he can ward off

1 their attacks, and he is forced into activity in order to avail himself of those appliances; and although he does not perhaps quite appreciate this necessity, it is doubtless beneficial to him. It may, I think, be very reasonably and fairly argued, that if mankind had none of these noxious pests (as he calls them) to torment him, whether he would not become indolent and neglectful of necessary cleanliness, not only of the habitation in which he lives, but also to his own personal discomfort. We are not to conclude hastily, because we suffer occasionally annoyance, and, under certain circumstances, even temporary pain, that an ultimate good cannot result from it; we should, I think more often than I am inclined to think we do, consider things not entirely according to our present sensations; even a present loss that we may sustain through natural agencies, we should look at, and inquire carefully into, and see whether we do not in reality enjoy some subsequent advantage in consequence. It is quite probable, nay, it is even certain, that we may fail to discover such benefit; but is it not, at the same time, possible that this arises solely from our limited faculties, which fail to enable us to see and comprehend results ?

It appears certain, when we take a comprehensive view of things, and see them in the light that points to the common good, that it is requisite that all things endowed with animal and vegetable life should


bear certain proportions to each other. Now if any particular species exceed those proportions, it will, in a greater or less degree, become obnoxious, and in degree disturb the requisite balance. Under such circumstances, it becomes necessary that such superabundance should be checked; we therefore see, throughout the entire system of animated nature, that all this is provided for by one creature preying upon another—"some few are sacrificed to the good of the whole.”

Now, if we look into the history of insects we find a most important part played by them in the great scheme of Nature ; there is scarcely a single plant that has not its appointed insect-frequently many that live

upon the same plant. Now, when we cultivate particular plants until we mature them into the edible vegetables we enjoy, we must not be surprised if we find some of these insects attacking our produce : it then becomes our appointed business to exert our faculties, and to invent means of guarding against such attacks; and who can estimate the benefit that may arise from the very circumstance of our faculties having been so sharpened ? It is under these circumstances that some of the most important discoveries are often made.

Who can doubt that it is a wise provision that races of insects should exist whose mission is to remove superabundant vegetation ? Not that I mean superfluous production, but a production that, having performed its appointed end, requires removal, and that removal is to be through the agency of insects. You have all read some account of the visitation and devastation of locusts, and of the destruction occasioned by their countless myriads. You must understand that these visitations only take place at intervals. There is a locust, common in the United States, which appears at regular intervals of seventeen years ; so that in some districts next year is now looked forward to as a locust year. But, as I have already observed, we must look, not to individual or to local losses, but to general benefits. In some regions of the globe such is the profuse exuberance of vegetable life, that a visitation of locusts clears whole districts that had become choked up through this teeming production; and we are told by residents in such districts, that the removal of this superabundance is frequently followed by the growth of new herbs, luxuriant and fresh grasses, suited as pasture for the wild cattle that inhabit such localities.

And thus it is we see the interest of individual man sacrificed for the general good ; and insects which he regards as so many pests will often be found most beneficial to him. Insects that feed upon the roots of grass, such as the larva of the common cockchafer, which does



so during a space of nearly four years, removes those grasses that are become coarse ; and so by these means room is made for fresh young shoots, which renders the pastures more nutritious to the cattle that graze upon them.

The earth-worm also plays a most important part in our fields, turning up the earth, and opening passages for air and moisture.

But I will now proceed to notice a few insects, the use of which will be apparent to every one ; and probably the insect which creates the ink-gall is as good an instance as can be selected. The ink-gall of commerce is not found in this country; it is the production of a species of cynips, called Cynips Galle tinctoria. It is an exceedingly common insect in Southern Europe ; the galls are collected in enormous quantities from oak-trees, and are an important article of commerce throughout Europe. From these galls the best kinds of ink have been manufactured for many years. Thousands of pounds' worth of these galls are imported into this country every year, and no discovery in chemistry has produced any article from which ink can be manufactured equal to that made from the gall of this little cynips.

Another most direct benefit which man derives from insects is the use, in medical science, of the blister-fly or blister-beetle, Cantharis vesicatoria. This valuable insect is principally imported from Spain ; it is occasionally found in this country, but is of rare occurrence ; in many parts of Europe it is found in immense numbers. profusion of this insect is to be regarded as a beneficent provision. Who can even imagine the benefit man has derived from the use of blisters prepared from these insects ? in how many million of cases has relief been afforded—in how many even life itself preserved ? I must remind you, that in tropical countries each one seems to be provided with insects equally beneficial as Cantharis vesicatoria : in India several species are used ; China has several, and the Brazils and South America are supplied with other species equally beneficial.

I am now going to allude to useful insects which every one will admit to be so, and none more readily than the ladies ; I am about to speak of the producers of silk. It would almost appear to us, in the present day, that silk-producing insects are a positive necessary;

and although such is not the case, strictly speaking, still we all readily admit silk to be one of the most splendid productions in nature. Silk is the product of an insect of foreign origin; and we are not, in estimating its value, to consider it merely in so far as it contributes to the comforts, necessities, or to the luxury of Europeans. We know well

Now the very



that it might have been possible to obtain materials for clothing from the wool of our flocks, and from the flax grown in our fields; but we

; are to look at it in other aspects, we are to consider necessities as they contribute to the universal good. Wool and flax we produce in this country; America has hitherto been the great emporium of cotton; and China and India the great silk-producing countries. Now, in the latter how many individuals obtain their living entirely from the cultivation of silk? There are those employed in planting, and attending to the great plantations of the mulberry-tree; those who collect the cocoons of the silk-producing moths, the Bombyx mori; the replacing of the moths upon the trees after the silk has been spun off; then there are those who prepare the raw material for the loom, for the purpose of home manufacture; then of that which is intended for the foreign market. It has been estimated that in China alone the silkworm-moth furnishes a livelihood for from two to three millions of individuals. We instantly appreciate the use of Bombyx mori when we have so estimated its value. But we must not forget that thousands are now employed in southern Europe in the cultivation of the silk

And let us not forget that after the silk is imported into Europe how many thousands obtain their living in the manufacture of it.

It appears that silk has been manufactured in China from the most ancient times; the oldest records speak of it as a common article of of dress; and yet it was not known in this country previous to the time of Queen Elizabeth ; its use and manufacture are now almost universal in civilized countries—modern science has discovered several moths, producers of silk, some little inferior to that of the Chinese Bombyx mori. It has been supposed possible to cultivate silk in this country, and the attempt has been made, and small quantities of silk have been manufactured; but the climate is not adapted to the insects, and the cost of production, even in the most favourable seasons, effectually debars its ever becoming a profitable speculation. In estimating

of any particular insect, we must not forget to take into account the fact that many, from which civilized man obtains no direct benefit, are of the greatest use to thousands of our less favoured fellow creatures ; neither must we forget that scientific research has, in many cases, discovered the means of supplying wants by other means, for which, for ages, man was entirely dependent upon insects.

This last remark cannot be better illustrated than by considering the produce of the honey bee. What value was formerly attached to the


the use

« VorigeDoorgaan »