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of age, quietness and repose become positive gratifications. In one important respect the advantage is with the old. A state of ease is, generally speaking, more attainable than a state of pleasure. This same perception of ease oftentimes renders old age a condition of great comfort, especially when riding at its anchor after a busy or tempestuous life. It is well described by Rousseau to be the interval of repose and enjoyment, between the hurry and the end of life. How far the same cause extends to other animal natures, cannot be judged of with certainty. The appearance of satisfaction, with which most animals, as their activity subsides, seek and enjoy rest, affords reason to believe, that this source of gratification is appointed to advanced , life, under all, or most of its various forms. In the species, with which we are best acquainted, namely, our own, I am far, even as an observer of human life, from thinking that youth is its happiest season,
much less the only happy one: as a Christian, I am willing to believe, that there is a great deal of truth in the following representation, given by a very pious writer, as well as an excellent man (Dr Percival of Manchester): “ To the intelligent and virtuous, old age presents a scene of tranquil enjoyments, of obedient appetites, of well-regulated affections, of maturity in knowledge, and of calm preparation for immortality. In this serene and dignified state, placed as it were on the confines of two worlds, the mind of a good man reviews what is past with the complacency of an approving conscience, and looks forward with humble confidence in the mercy of God, and with devout aspirations, towards his eternal and increasing favour.”—What is seen in different stages of the same life, is still more exemplified in the lives of different animals. Animal enjoyments are infinitely diversified. The modes of life, to which the organization of different animals respectively determinesthem, are notonly of various, but of opposite kinds. Yet each is happy in its own. For instance, animals of prey live much alone ; animals of a milder constitution, in society. Yet the herring, which lives in shoals, and the sheep, which lives in flocks, are not more happy in a crowd, or more contented amongst their compa
nions, than is the pike, or the lion, with the deep solitudes of the pool or the forest. At this moment,-in every given moment of time,-how many myriads of animals are eating their food, gratifying their appetites, ruminating in their holes, accomplishing their wishes, pursuing their pleasures, taking their pastimes! In each individual, how many things must go right for it to be at ease ; yet how large a proportion out of every species is so in every assignable instant ! Paley.
ON THE PARENTAL INSTINCT OF INSECTS.
INSECTS undergo as severe privations, as the largest quadrupeds, in nourishing their offspring; expose themselves to as great risk in defending them; and, in the very article of death, exhibit as much anxiety for their preservation. A very large proportion of them, indeed, are doomed to die before their young come into existence ; but these, like affectionate parents in similar circumstances, employ their last efforts in providing for the children, that are to succeed them.-Observe the motions of that common white butterfly, which fying from herb to herb. You perceive that it is not food she is in pursuit off; for flowers have no attraction for her. Her object is the discovery of a plant, that will supply the sustenance appropriated by Providence to her young, upon which to deposit her
Her own food has been honey drawn from the nectary of a flower. This, therefore, or its neighbourhood, we might expect, would be the situation she would select for them. But no: as if aware that this food would be to them poison, she is in search of some plant of the cabbage tribe. But how is she to distinguish it from the surrounding vegetables ? She is taught of God! Led by an instinct far more unerring than the practised eye of the botanist, she recognises the desired plant the moment she approaches it, and upon this she places her precious burden; yet not without the further
precaution of ascertaining, that it is not pre-occupied by the eggs of some other butterfly. Having fulfilled this duty, from which no obstacles short of absoluteimpossi. bility, no danger, however threatening, can divert her, the affectionate mother dies.—The dragon-fly is an inhabitant of the air, and could not exist in water; yet, in this element, which is alone adapted for her young, she ever carefully drops her eggs.—The larvæ of the gadily are destined to live in the stomach of the horse. How shall the parent, a two-winged fly, conduct them thither? By à mode truly extraordinary. Flying round the animal, she curiously poises her body for an instant, while she glues a single egg to one of the hairs of his skin, and repeats this process until she has fixed, in a similar
These, after a few days, on the application of the slightest moisture attended by warmth, hatch into little grubs. Whenever, therefore, the horse chances to lick any part of his body, to which they are attached, the moisture of the tongue discloses one or more grubs, which, adhering to it by means of the saliva, are conveyed into the mouth, and thence find their way into the stomach. But here a question occurs to you.
It is but a small portion of the horse's body, which he can reach with his tongue: what, you ask, becomes of the eggs deposited on other parts ? I will tell you how the gadfly avoids this dilemma ; and I will then ask you, if she does not discover a provident forethought, a depth of instinct, which almost casts into shade the boasted reason of man. She places her eggs only on those parts of the skin, which the horse is able to reach with his tongue : nay, she confines them almost exclusively to the knee or the shoulder, which he is sure to lick. What could the most refined reason, the most precise adaptation of means to an end, do more?-Nor less admirable is the parental instinct of that vast tribe of insects known by the name of ichneumons, whose young are destined to feed
upon the living bodies of other insects. You see this animal alight upon the plants, where the caterpillar (which is the appropriate food for her young), is to be met with, run quickly over them, carefully examining, every leaf, and, having found the unfortunate object of her search, insert her sting into its flesh, and there deposit an egg. In vain her victim, as if conscious of its fate, writhes its body, spits out an acid fluid, and brings into action all the organs of defence, with which it is provided. The active ichneumon braves every danger, and does not desist, until her courage and address have ensured subsistence for one of her future progeny. Perhaps, however, she discovers that she has been forestalled by some precursor of her own tribe, that has already buried an egg in the caterpillar she is examining. In this case she leaves it, aware that it would not suffice for the support of two, and proceeds in search of some other yet unoccupied. The process is of course varied in the case of those minute species, of which several, sometimes as many as 150, can subsist in a sin. gle caterpillar. The little ichneumon repeats her operations, until she has darted into her victim the requisite number of eggs. The larvæ, hatched from the eggs thus ingeniously deposited, find a delicious banquet in the body of the caterpillar, which is sure eventually to fall a victim to their ravages. So accurately, however, is the supply of food proportioned to the demand, that this event does not take place until the young ichneumons have attained their full growth. In this strange and apparently cruel operation, one circumstance is truly remarkable. The larva of the ichneumon, though every day, perhaps for months, it gnaws the inside of the caterpillar, and though at last it has devoured almost every part of it except the skin and intestines, carefully all this time avoids injuring the vital organs, as if aware that its own existence depends on that of the insect, on which it preys. Thus the caterpillar continues to eat, to digest, and to move, apparently little injured, to the last, and only perishes when the grub within it no longer requires its aid.—Another tribe of ichneumons, whose activity and perseveranceare equally conspicuous, like the insidious cuckoo, contrive to introduce their eggs into the nests, in which bees and other insects have deposited theirs. With this view, they are constantly on the watch, and the moment the unsuspecting mother has quitted her cell, for the purpose of collecting a store of food or materials, glide into it and
the of a future assassin of the larva, that is to spring from that deposited by its side. There is a spider common under clods of earth, which may at
leave an egg,
once be distinguished by a white globular silken bag, about the size of a pea, in which she has deposited her eggs, attached to the extremity of her body. Never miser clung to his treasure with more tenacious solicitude, than this spider to her bag. Though apparently a considerable encumbrance, she carries it with her every where. If you deprive her of it, she makes the most strenuous efforts for its recovery; and no personal danger can force her to quit the precious load. Are her efforts ineffectual ?.
-a stupefying melancholy seems to seize her, and, when deprived of the first object of her cares, existence itself seems to have lost its charms. If she succeeds in regaining her bag, or you restore it to her, her actions demonstrate the excess of her joy. She eagerly seizes it, and with the utmost agility, runs off with it to a place of security. Bonnet put this wonderful attachment to an affecting and decisive test. He threw a spider with her bag into the cavern of a large ant-lion, a ferocious insect, which conceals itself at the bottom of a conical hole constructed in the sand, for the purpose of catching any unfortunate victim, that may chance to fall in. The spider endeavoured to run away, but was not sufficiently active to prevent the antlion from seizing her bag of eggs, which it attempted to pull under the sand. She made the most violent efforts to defeat the aim of her invisible foe, and, on her part, struggled with all her might. The gluten, however, which fastened her bag, at length gave way, and it separated; but the spider instantly regained it with her jaws, and redoubled her efforts to rescue the prize from her opponent. It was in vain ; the ant-lion was the stronger of the two, and, in spite of all her struggles, dragged the object of contestation under the sand. The unfortunate mother might have preserved her own life from the enemy; she had but to relinquish her bag, and escape out of the pit; and it was only by force that Bonnet at length withdrew her from the unequal conAict. But the bag of eggs remained with the assassin ; and, though he pushed her repeatedly with a twig of wood, she still persisted in continuing on the spot. Life seemed to have become a burden to her, and all her pleasures to have been buried in the grave, which