Abbildungen der Seite

select description. Some of the ant tribes feed chiefly upon liquor, which is yielded to them by the aphis, whole flocks of which insect, if we may use the expression, they appropriate to themselves, tend and support, as we do our flocks of sheep and our herds of cattle. But what, perhaps, is not the least surprising passage in the history of ants is this, that there are races of them which have their negro slaves; regular whites, who, reposing in indolence themselves, compel the less fortunate nation of blacks to do for them all the drudgery which they require. The wasp, who is pursued with unrelenting hostility by every body that sees him,--the terror of all nurses,-is, nevertheless, a most industrious and most excellent manufacturer of paper.

These are a few of the curiosities of history, belonging to insects, which would repay, in the way of amusement, the attention of the most careless reader. But the transformations which insects undergo, furnish materials for reflection of a still more important kind. A deformed, leaf-devouring, loathsome looking thing crawls along our path in the spring, and, if we do not extinguish the little spark of life that warms him, he sports about our garden before the summer is over, in the form of a beauteous butterfly, decorated with a pair of wings so tastefully painted, that no artist can rival the splendour of their colouring. There is in the south of Europe an insect called the ant-lion, which, though apparently the most helpless of all creatures, has a most formidable appearance. It contrives, by laying pit-falls, to live the life of a murderer for two years, during which period it resembles a wood-louse. This, however, is but its state of probation, as a larva. When the appointed time arrives, it repents of all its former habits, and retires into the earth, where it surrounds itself with a case, the inside of which it ornaments with a pearl-coloured satin, of the most exquisite delicacy and beauty, the produce of its own silk and loom. In this elegant hermitage the penitent remains about two months, when not only his form, but his nature, is completely metamorphosed; he puts on four wings, and re-visits the world, a creature of purity, innocence, and gaiety, as a fly of a very brilliant description. As

suredly there are, in these changes, a pledge and a warning for ! man, of that great transformation which awaits him when his ap

pointed moment arrives. If it be said that this death and burial and resurrection, under another form, of insects, be necessary to the propagation of their race, we must only therefore the more admire the goodness of Him who bas ordained such a law, from which man cannot fail to derive the hope that he, also, after descending to the earth, may rise a newly-formed and purified creature, and destined for higher worlds than that from which, in his larva state, he now draws his support.

There are a few, and but a few, technical expressions which the reader should make himself master of before he plunges into the history of insects. It will be no harm to him to know that the word itself is borrowed from the Latin Insectum, or Intersectum, that is "cut between,” the bodies of these animals being apparently divided into two or more parts or notches, held together, as it were, by ligatures. In some,-the bee, for instance,-the mouth is elongated, and called a proboscis. Almost all insects have two Antenna, or feelers, the utility of which, says the history published by Mr. Murray, may be doubted. We are surprised that the intelligent author of that work should have fallen into such a mistake. The Antenna serve not only as hands, but as the organs of language among bees and ants, whereby their labours are often directed, and all extraordinary incidents, as the death of a queen, or the invasion of a formidable enemy, is communicated. The first state of the insect is the egg; the second, the larva, which means grub, worm, or caterpillar; the third, the chrysalis, aurelia, or nymph, in which the insect is sketched out in the shape which becomes fully displayed in the Imago, his fourth and perfect state.

The paramount object of the insect world is to propagate their species; the care with which they attend to their eggs, and to their young, is, with many races of these animals, more a passion than an instinct. Though the wasp is by no means popular with us, it is impossible not to feel an interest in the affectionate wariness with which even the most solitary of the tribe, endeavours to preserve its egg from destruction,

* In September, 1828,' says Mr. Rennie, the author of the very delightful volume on Insect Architecture, “a common species of solitary Mason-wasp (Odynerus, Latr.) was observed by us on the east wall of a house at Lee, in Kent, very busy in excavating a hole in one of the bricks, about five feet from the ground. Whether there might not bave been an accidental hole in the brick, before the wasp commenced her labours, is unknown, as she had made considerable progress in the work when first ! observed ; but the brick was one of the hardest of the yellow sort made in this neighbourhood. The most remarkable circumstance in the process of hewing into the brick, was the care of the insect in removing to a distance the fragments which from time to time she succeeded in detaching. It did not appear to suit her design to wear down the brick, particle by particle, as the furniture beetle (Anobium pertinax) does, in making its pin-hole galleries in old wood. Our wasp-architect, on the contrary, by means of her strong tranchant-loothed jaws, severed a piece usually about the bigness of a mustard seed. It might have been supposed that these fragments would have been tossed out of the hole as the work proceeded, without further concern ; as the mole tosses above ground the earth which has been cleared out of its subterranean gallery. The wasp was of a different opinion ; for it was possible that a heap of brick chips, at the bottom of the wall, might lead to the discovery of her nest by some of her enemies, particularly by one or other of the numerous tribe of what are called ichneumon flies. This name is given to them, from the similarity of their habit of destroying eggs to that of the little animal which proves so formidable an enemy to the multiplication of the crocodile of Egypt. They may be also denominated cuckoo fies, because, like that bird, they

thrust their egg into the nest of another species. These flies are continually prowling about and prying into every corner, to find, by stealth, a nidus for their eggs. It might have been some such consideration as this which induced the wasp to carry off the fragments as they were successively detached. That concealment was the motive, indeed, was proved ; for one of the fragments which fell out of the hole by accident, she immediately sought for at the bottom of the wall, and carried off like the rest. It was no easy matter to get out one of the fragments, as may readily be conceived when the size of the insect is compared with that of the entrance, of which this (O) is the exact size, as taken from the impression of a bit of dough upon the hole when finished. It was only by seizing the fragment with her jaws, and retreating backwards, that the matter could be accomplished; though, after the interior of the excavation was barely large enough to admit of her turning round, she more than once attempted to make her exit head-foremost, but always unsuccessfully. The weight of the fragments removed did not appear to impede her flight, and she generally returned to her task in about two or three minutes.

Within two days the excavation was completed ; but it required two other days to line it with a coating of clay, to deposit the eggs, two in number, and, no doubt, to imprison a few live spiders or caterpillars, for the young when hatched,-a process which was first observed by Ray and Willoughby, * but which has since been frequently ascertained. In the present instance, this peculiarity was not seen; but the little architect was detected in closing up the entrance, which was formed of a layer of clay more than double the thickness of the interior lining. In November following, we hewed away the brick around this nest, and found the whole excavation was rather less than an inch in depth.'—pp. 26—28.

Generally speaking, the mason-wasp trusts to his teeth alone as the great instrument of excavation ; but it appears, from an experiment made by Réaumur, to whom the world is indebted for much of the knowledge that we possess concerning insects, that this little creature, when it meets with a particularly hard substance, has the power of voiding upon it a drop of liquid, which softens the material

, and considerably facilitates the work man's labour. Thus the mason-wasp may have taught Hannibal the means by which he is said to have waged battle against the rocks of the Alps, which impeded his descent upon Italy.

carpenter-wasps dig not only holes, but galleries, in timber, and, by means of the saw-dust, if we may say so, which they create in the course of their labours, they form walls or partitions between the cells required for their purpose. The art of manufacturing paper is a point of perfection, 'at which only the social wasps appear to have arrived. Their proceedings deserve a moment's

'In their general economy, the social, or republican wasps, closely resemble the humble-bee, (Bombus,) every colony being founded by a single female, who has survived the winter, to the rigours of which all her



[blocks in formation]
[ocr errors]

summer associates of males and working-wasps uniformly fall victims. Nay, out of three hundred females, which may be found in one vespiary, or wasp's nest, towards the close of autumn, scarcely ten or a dozen survive till the ensuing spring, at which season they awake from their hybernal lethargy, and begin, with ardour, the labours of colonization.

* Her first care, after being roused to activity by the returning warmth of the season, is to discover a place suitable for her intended colony; and, accordingly, in the spring, wasps may be seen prying in to every hole of a hedge-bank, particularly where field-mice have burrowed. Some authors report that she is partial to the forsaken galleries of the mole, but this does not accord with our observations, as we have never met with a single vespiary in any situation likely to have been frequented by moles. But though we cannot assert the fact, we think it highly probable that the deserted nest of the field-mouse, which is not uncommon in hedge banks, may be sometimes appropriated by a mother-wasp, as an excavation convenient for her purpose. Yet, if she does make choice of the burrow of a field-mouse, it requires to be afterwards considerably enlarged in the interior chamber, and the entrance-gallery very much narrowed.

• In case of need, the wasp is abundantly furnished by nature with instruments for excavating a burrow out of the solid ground, as she, no doubt, most commonly does, digging the earth with her strong mandibles, and carrying it off, or pushing it out, as she proceeds. The entrancegallery is about an inch or less in diameter, and usually runs in a winding or zig-zag direction, from one to two feet in depth. In the chamber to which this gallery leads, and which, when completed, is from one to two feet in diameter, the mother-wasp lays the foundations of her city, begining with the walls.

* The building materials employed by wasps were long a matter of conjecture to scientific inquirers; for the bluish-grey, papery su'stance of the whole structure has no resemblance to any sort of wax employed by bees for a similar purpose. Now that the discovery has been made, we can with difficulty bring ourselves to believe that a naturalist so acute and indefatigable as M. Réaumur, should have, for twenty years, as he tells us, endeavoured, withont success, to find out the secret. At length, however, his perseverance was rewarded. He remarked a female wasp alight on the sash of his window, and begin to gnaw the wood with her mandibles; and it struck him at once that she was procuring materials for building. He saw her detach from the wood a bundle of fibres, about a tenth of an inch in length, and finer than a hair ; and as she did not swallow these, but gathered them into a mass with her feet, he could not doubt that his first idea was correct. In a short time she shifted to another part of the window-frame, carrying with her the fibres she had collected, and to which she continued to add, when he caught her, in order to examine the nature of her bundle ; and he found that it was not yet moistened or rolled into a ball, as is always done before employing it in building. In every other respect it had precisely the same colour, and fibrous textures, as the walls of a vespiary. It struck him as remarkable, that it bore no resemblance to wood gnawed by other insects, such as the goat-moth caterpillar, which is granular, like saw-dust. This would not have suited the design of the wasp, who was well aware that fibres of some length form a stronger texture. He even discovered, that before detaching the fibres, she bruised them (les charpissoit) into a sort of lint (charpie) with her 'mandibles. All this the careful naturalist imitated, by bruising and paring the same wood of the window-sash with his pen-knife, till he succeeded in making a little bundle of fibres scarcely to be distinguished from that collected by the wasp.

• We have ourselves frequently seen wasps employed in procuring their materials in this manner, and have always observed that they shift from one part to another more than once in preparing a single load; a circumstance which we ascribe entirely to the restless temper peculiar to the whole order of hymenopterous insects. Réaumur found that the wood which they preferred was such as had been long exposed to the weather, and is old and dry. White, of Selborne, and Kirby and Spence, on the contrary, maintain that

obtain their

paper from sound timber, hornets only from that which is decayed.* Our own observations, however, confirm that statement of Réaumur, with respect to wasps, as, in every instance which has fallen under our notice, the wood selected was very much weathered ; and, in one case, an old oak post, in a garden at L-e, in Kent, half destroyed by dry-rot, was seemingly, the resort of all the wasps in the vicinity. In another case, the deal bond in a brick wall, which had been built thirty years, is, at this moment, (June, 1829), literally striped with the gnawings of wasps, which we have watched at the work for hours together.t

* The bundles of ligneous fibres thus detached, are moistened, before being used, with a glutinous liquid, which causes them to adhere together, and are then kneaded into a sort of paste, or papier maché. Having prepared some of this material, the mother-wasp begins first to line with it the roof of her chamber, for wasps always build downwards. The round ball of fibres which she has previously knearled up with glue, she now forms into a leaf, walking backwards, and spreading it out with her mandibles, her tongue, and her feet, till it is as thin almost as tissue paper.

One sheet, however, of such paper as this would form but a fragile ceiling, quite insufficient to prevent the earth from falling down into the nest. The wasp, accordingly, is not satisfied with her work till she has spread fifteen or sixteen layers, one above the other, rendering the wall altogether nearly two inches thick. The several layers are not placed in contact, like the layers of a piece of pasteboard, but with small intervals, or open spaces, between, appearing somewhat like a grotto built with bivalve shells, particularly when looked at on the outside. This is probably caused by the insect working in a curvilineal manner.

• Having finished the ceiling, she next begins to build the first terrace of her city, which, under its protection, she suspends horizontally, and not like the combs in a bee-hive, in a perpendicular position. The suspension of which we speak is also light and elegant, compared with the more heavy union of the hive-bees' combs. It is in fact a hanging floor, immoveably secured by rods of similar materials with the roof, but rather stronger. From twelve to thirty of these rods, about an inch or less in length, and a quarter of an inch in diameter, are constructed for the suspension of the

* Réaumur, vol. vi. bottom of page 182 ; Hist. of Selb. ii. 228 ; and Introd. to Entomol. i. 504, 5th edition.

† J. R.

« ZurückWeiter »