Worker (insect)

“ This stupendous labour of construction and provisioning, this labour that absorbs the insect's whole life, is the work of the mother only, who wears herself out at her task. The father, intoxicated with sunlight, lies idle on the threshold of the workshop, watching the heroic female at her work, and regards himself as excused from all labour when he has plagued his neighbours a little.
Does he never perform useful work? Why does he not follow the example of the swallows, each of whom brings a fair share of the straw and mortar for the building of the nest and the midges for the young brood? ”

“ What we call parasitism in insects is really a kind of hunting. The Mutilla, for instance, is a huntress, and her prey is the grub of another kind of Wasp, just as the game of this other kind of Wasp may be a Caterpillar or a Beetle. When it comes to this, we are all hunters, or thieves, whichever way you look at it, and Man the greatest of all. He steals the milk from the Calf, he steals the honey from the children of the Bee, just as the Gray Fly takes the food of the Wasps’ babies. She does it to feed her children; and Man helps himself to everything he can find to feed his. ”

“ In this process the entire old skin is shed, an operation well worth seeing. Under the old coat a new one has formed, which being larger, accommodates itself to the insect's increased size. The larval stage is in the case of many insects the active time when, if they are vegetable feeders, they injure crops.
When the larva has completed its growth it changes into a pupa. Some insects pass this third stage inside of silken cases they spin about themselves, others, after shedding the larval skin, find themselves each clad in a sort of horny coat of mail. We call these chrysalides. ”

“ Has personal experience not fully convinced us that the mere examination of the insect can tell us nothing about its particular industry? The baskets on its legs and the brush on its abdomen will certainly inform us that it collects honey and pollen; but its special art will remain an utter secret, notwithstanding all the scrutiny of the microscope. In our own industries, the plane denotes the joiner, the trowel the mason, the scissors the tailor, the needle the seamstress. Are things the same in animal industry? ”

“ The largest holes are filled up with detritus of all kinds. Then these materials are agglutinated by a special secretion. The larva overlays the interior of its tube with a covering of soft silk which renders the cylinder watertight and consolidates the earlier labours. The insect is thus in possession of a safe retreat. Resembling some piece of rubbish, it completes its metamorphosis in peace, undisturbed by the carnivora of the stream. ”

“ This type of insect gradually gave rise to the orders which now contain the largest number of species, including the beetles, moths, and flies. In many lines of this neuropteroid branch, as it is called, the larva has become adapted to a mode of life quite different from that of the adult. Many fly larvae, for example, live in rotting organic material or live as parasites within the tissues of other kinds of insects, whereas the adult flies often feed at flowers on pollen and nectar, visiting the site of the larval habitat only to lay eggs. ”

“ Urged by the labour of the ovaries, the insect resumes its interrupted work.
In certain cases, I see it, still on the surface, destroying its ball, ripping it up, cutting it to pieces, shredding it. This is not in the least the act of one in despair who, finding herself a captive, breaks the cherished object in her bewilderment. It is an act of wise hygienics. A scrupulous inspection of the morsel gathered in haste, among lawless competitors, is often necessary, for supervision is not always easy on the harvesting-spot itself, in the midst of thieves and robbers. ”

“ We went back to his office, and there he handed me a circular advertising his business as an exterminator of insects. "I undertake, by the particular job or on yearly contract, to exterminate all varieties of insects from your furniture, your clothing, your furs, your house. Moths a specialty. Also, for sale in pound, half pound aid quarter pound packages, or in any quantity, Muselle's Magic Insecticide, positively guaranteed as the best insect powder in the universe. ”

“ These jaws then had their turn. And that was the end of the May-fly.
Mary was rather shocked when she saw the dragon first use its "catcher." She wanted to rescue the poor May-fly. But after all she has got pretty well used to seeing tragedies in insect life. They seem to be necessary and normal. Many insects depend upon other animals for food, just as we do. Only fortunately we don't have to catch and kill our own steer or pig or lamb or chicken. We turn the bloody business over to men who like—well, at least, who do it for us. ”

“ The number of workers increases largely during the summer, and so hard do the insects work that the life of an individual may last only a few weeks. On the approach of winter the males, having no further function to perform for the community, are refused food-supplies by the workers, and are either excluded or banished from the hive to perish. Such ruthless habits of the bee-commonwealth, no less than the altruistic labours of the workers, are adapted for the survival and dominance of the species. ”

“ In some groups the duties of the workers are subdivided among classes that differ in size and equipment. It is these female workers, or their correlatives among the solitary bees and wasps, that sting, their useless ovipositors having been transformed by the addition of poison into deadly weapons by which they procure their prey, or defend themselves, or both. It is this division of labor, and attendant habits, that especially characterize the higher Hymenoptera, and give to the order the supreme rank it occupies among insects. ”

“ The insect has departed in the night, having finished its business there. It is a nomad, a night-walker, which leaves its dwelling without regret and easily acquires another. Often, on the other hand, the insect will be found at the bottom of the burrow; sometimes a male, sometimes a female, but always alone. The two sexes, equally zealous in excavating their burrows, work apart without collaboration. This is no family mansion for the rearing of offspring; it is a temporary dwelling, made by each insect for its own benefit. ”

“ These insect-killers, who live on their prey, strike the game dead at once by stinging the nerve-centers of the neck; the paralyzers, on the other hand, who wish to keep the food fresh for their larvæ, destroy the power of movement by stinging the game in the other nerve-centers, lower down. They do not acquire this knowledge, they have it as soon as they are born. And they teach those of us who think that there is something behind it all, that there is Some One who has planned things for insects and men alike. ”

“ The full-grown male has been described above. It is usually easy to procure specimens, provided the pupæ are obtained. If any of these, in their coverings, are put into pillboxes with glass tops, or any place where light reaches them, they will generally produce the full-grown insect sometimes in a few days, sometimes after several weeks. ”

“ The singular pair of hooks on its back are used as the flukes of an anchor to sustain the insect in the position it assumes at the mouth of the cell.
Larva of the Tiger-Beetle.
Mention has already been made in the previous chapter of the insects called Ichneumons, which deposit their eggs in the bodies of the larvæ of [119] other insects. These, when hatched, are also to be reckoned among the larvæ which prey upon flesh, since they devour the bodies of the larvæ in which they have been deposited. They are thus most useful to mankind in destroying the devourers of his vegetable food. ”

“ Hence no rendezvous at a general meeting-place; no living among neighbours, no tribes stimulating themselves by mutual example—only isolation where chance has led the Sphex—solitary labour, unenthusiastic, though always conscientious. First of all prey is sought, attacked, and paralysed. Then comes making the burrow. A favourable spot is chosen as near as possible to that where lies the victim, so as to abridge the toil of transport, and the cell of the future larva is rapidly hollowed to receive an egg and food as soon as possible. ”

“ It is even possible in some cases, the water flea, for example, for the female to produce young without the necessity of fertilization by the male. In order to perform the necessary work to insure food supplies for the winter other insects have developed highly specialized workers, especially fitted to do particular kinds of labor. ”

“ Warned by the stench, which travels far and wide, a host of insects are flying hither; such insects as dissect the corpses of frogs, adders, lizards, hedgehogs, moles and field-mice—creatures that the peasant finds beneath his spade and throws disembowelled on the path. They fall upon the great leaf, whose livid purple gives it the appearance of a strip of putrid flesh; they dance with impatience, intoxicated by the corpse-like odour which to them is so delicious; they roll down its steep face and are engulfed in the capsule. After a few hours of hot sunlight the receptacle is full. ”

“ With the social wasps and social bees the workers are all infertile females and are smaller than the fertile forms; with the termites there are besides the fertile males and females, which are winged, workers which are wingless, and also peculiar wingless individuals called soldiers which have very large jaws and whose business it is to fight off attacking enemies of the community. Among the ants the workers are also wingless, while the males and females are winged. The worker ants in many species are of two kinds, so-called worker majors and worker minors, differing markedly in size. ”

“ When a bag made beforehand is used, the points must be rounded, and in tying the piece of gauze over the branch care must be taken to pull out all creases and folds, or the insect will be sure to get into them and either die or be killed by spiders from the outside of the bag. It is better to put more than one female in the same cage. ”

“ Among these insects, the most numerous are the workers: their size is that of a large ant, and their duties are to excavate galleries, to search for provisions, and to take care of the eggs, the larvæ, and the pupæ. 406 The workers have a rounded head and short mandibles, and are blind. The soldiers, less numerous, have an enormous head—nearly as big as the rest of their body—very strong, crossed mandibles, and are blind like the workers. Anatomy showed M. Lespès that both are neuters—that is, the soldiers, males, and the workers, females—with aborted organs. ”

“ Leaving its tunnel the insect rises to the surface, the thorax is lifted above the water which retreats from it on all sides, the skin cracks open at the back and the insect slowly extricates itself in a similar manner to the mosquito. In about ten minutes' time the wings are sufficiently hardened for use and the insect then flies ashore, but we may occasionally notice, beside their old pupa-skins, drowned individuals which have failed to effect a successful emergence. ”

“ There were some who, in the course of their rude task as diggers and rollers, wore out that delicate, cumbrous, useless member; and, finding themselves better equipped for their work by this accidental amputation, they bequeathed it to their successors, to the great benefit of the race. The present insect profits by the improvement obtained by a long array of ancestors, and, acting under the stimulus of vital competition, gives permanence to an advantageous condition due to chance. ”

“ It is noteworthy that in these short-lived insects the male is often provided with elaborate sense-organs which, we may believe, assist him to find a mate with as little delay as possible; the male may-fly has especially complex eyes, while the feelers of the male silk-moth or eggar are comb-like or feathery, the branches bearing thousands of sensory hairs. A box with a captive living female of one of these moths, if taken into a wood haunted by the species becomes rapidly surrounded by a swarm of would-be suitors, attracted by the odour emitted from the prisoner's scent-glands. ”

“ The workers die suddenly. They come to the surface, slip down, fall on their backs and rise no more, as if they were struck by lightning. They have had their day; they are slain by age, that merciless poison. Even so does a piece of clockwork become motionless when its mainspring has unwound its last spiral.
The workers are old: but the mothers are the last to be born into the nest, and have all the vigour of youth. ”

“ When untouched, the insect exerts itself and consequently uses up its reserves. When paralysed, it has merely the feeble, internal movements which are inseparable from any organism; and its substance is economized in proportion to the weakness of the action displayed. In the first case, the animal machine is at work and wears itself out; in the second, it is at rest and saves itself. There being no nourishment now to repair the waste, the moving insect spends its nutritive reserves in four days and dies; the motionless insect does not spend them and lives for eighteen days. ”

“ And it is of interest to note that this somewhat degraded type of larva is remarkably constant through a great series of families—gall-flies, ichneumon-flies, wasps, bees (fig. 18) , ants—that vary widely in the details of their structure and in their habits and mode of life. Almost without exception, however, they make in some way abundant provision for their young. The feeble, helpless, larva is in every case well sheltered and well fed; it has not to make its own way in the world, as the active armoured larva of a ground-beetle or the caterpillar of a butterfly is obliged to do. ”