Swarming (insect)

“ The lure is irresistible. None will break free from the swarm until the evening, or perhaps the next day, when the heady fumes will have evaporated. Then the units of the swarm disengage themselves from their mutual embraces, and slowly, as though regretfully, take flight and depart. At the bottom of this devil's purse remains a heap of the dead and dying, of severed limbs and wing-covers torn off; the inevitable sequels of the frantic orgy. Soon the woodlice, earwigs, and ants will appear to prey upon the injured. ”

“ When one of these miniature monsters becomes full-grown, it ceases its depredations on the aphid flocks, enters a period of quietude, and fixes the rear end of its body to a leaf by exuding a glue from the extremity of its abdomen. Then it sheds its skin, which shrinks down over the body and forms a spiny mat ad- hering to the leaf and supporting the former occupant by only the tip of the body (Fig. 132 E) . With the shedding of the skin, the insect has changed from a larva to a pupa, and after a short rime it will transform into a perfect lady-beetle like its father or mother. ”

“ Sometimes the burrow contains nothing but the well-sinker surprised at its work: sometimes—and not rarely—the hermit will be found embracing a small subterranean fungus, entire or partly consumed. It presses it convulsively to its bosom and will not be parted from it. This is the insect's booty: its worldly wealth. Scattered crumbs inform us that we have surprised the beetle at a feast. ”

“ It is constantly seen wading in the shallows, digging up little slippery insects, the peculiar form of the bill enabling it to work them easily out of the sand. When feeding, it puts its head under the water to seize the insect at the bottom, then lifts it up quickly, making a rapid gobbling, as if swallowing a wriggling worm. ”

“ Imitations of such can be used throughout the summer months. There are many insects that do not breed in water, yet are successful baits. As a rule, insects that appear in large numbers, whether they belong to land or water, are the proper ones for imitation. Solitary specimens, although dear to the heart of an entomologist, are eyed by the fish with haughty indifference. Water is a great attraction for all insect tribes. The banks of streams constitute the favorite hunting-ground for insect collectors, where they compete with the fish, those practical entomologists, in collecting. ”

“ Like the eggs and young of other insects, however, those of the mole-cricket are exposed to depredation, and particularly to the ravages of a black beetle which burrows in similar localities. The mother insect, accordingly, does not think her nest secure till she has defended it, like a fortified town, with labyrinths, intrenchments, ramparts, and covert ways. In some part of these out-works she stations herself as an advanced guard, and when the beetle ventures within her circumvallations, she pounces upon him and kills him. ”

“ Mosquitoes revel in this congenial atmosphere, as do also the blue-tail fly, and a species of biting insect like the common house-fly, while gallinippers, gnats, ants, and biting sand-fleas, (which play second fiddle to the old-fashioned iron-clad chaps, their bites making one squirm as if twinged by a bad conscience,) and grey-backs, all attack the hapless sleeper in succession, in a body, by detail, in squads, battalion,—in brigades drawn up in echelon—in front, flank and rear. ”

“ These take their rise from the mud at the bottom, and, extending upwards to a distance of three or four inches, afford the larva a convenient retreat from all enemies. These insects are occasionally seen swimming laboriously through the water with a peculiar zigzag motion. When out of their burrows they have considerable difficulty in keeping beneath the surface, and may be often observed floating helplessly with their exposed portions quite dry; in fact the whole integment of the insect appears to have a peculiar power of resisting the water. ”

“ They assemble in small flocks, climbing rapidly along the rough bark of the pitch-pine, rapping here and there, with their wedgelike beaks, to scare some drowsy insect; inducing it to rush out, to be nipped, or speared, with the barbed tongue, ere half-awake; others, sitting on the topmost branches of the oaks and pines, continually darted off after some fugitive moth or other winged insect, capturing it much in the fashion of the flycatchers. The harsh and discordant voice is made up for in beauty of plumage. ”

“ The insect world, which during the hot weather was held in such small account, now holds itself supreme. Convinced themselves that entomology is the finest study in the world, the insects carry their doctrine at their tails’ point to convince others. Every one must learn and be quite clear about the difference between a black mosquito with grey spots, and a grey mosquito with black spots. There must be no confusion between a fly which stings you if you touch it, and a fly which if it touches you stings. No one can pretend to ignore the insect invaders — the bullety beetles and maggoty ants. ”

“ In hot countries the great business of removing corrupt animal matter, which the vulture and hyæna imperfectly perform, is effected with certainty and speed by the myriads of insects that spring from the eggs deposited in every carcase 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. ”

“ The Biological Survey has ascertained and gives wide publicity to the fact that at least 43 kinds of birds prey upon this destructive insect. It has discovered that 57 species of birds feed upon scale-insects—dreaded enemies of the fruit grower. ”

“ When this is finished, all except a round hole, it brings seven or eight caterpillars or spiders, each of which is rendered insensible, but not killed, by the fluid from its sting. These it deposits in the cell, and then one of its own larvae, which, as it grows, finds food quite fresh. The insects are in a state of coma, but the presence of vitality prevents putridity, or that drying up which would otherwise take place in this climate. By the time the young insect is full grown and its wings completely developed, the food is done. ”

“ 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. ”

“ I have often kept specimens of these larvæ in vessels of water and noticed their predaceous habits; they feed on the larvæ of other water insects, but are not able to destroy fish, not being furnished with jaws or bodies nearly so strong as the perfect insect itself possesses. When the larva wishes to turn into its pupa state, it makes a round hole in the bank of the pond it inhabits, and there undergoes its change, turning into a full-grown beetle in about three [Pg 31] weeks' time. ”

“ At first a creeper and sharp-eyed inspector of hidden crannies, we afterwards discern no less in him, and upon the slightest provocation, a tyrant on the wing, thereby proving a general adaptability to and utility in his calling at all stages of the game—a constant warfare directed against the insect horde to which he devotes himself most assiduously at all times, and it is really astonishing the amount of the minute forms of insect life these little birds will consume. ”

“ 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. ”

“ They even attack wasps’ nests, which they cut to pieces and then drag out the larvæ. They bite and sting severely, and the traveller who accidentally steps into a horde of them will soon be overrun, and must make his escape as quickly as possible. They do not confine themselves to the ground, but swarm up bushes and low trees, hunting every branch, and clearing them of all insect life. Sometimes a band will enter a house, like the driver ants in Africa, and clear it of cockroaches, spiders, centipedes, and other insects. ”

“ 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. ”

“ After having covered your head with a veil, if the swarm has settled in a difficult place, and you are afraid of being stung, you hold the hive under the cluster of bees and make them fall into it, either by shaking the branch to which the swarm is attached, very hard, or by means of a small broom, or even with the hand, for then they very rarely sting: it is hardly ever necessary to take any precautions in approaching them, except for swarms which have been fixed for many hours, or since the day before. ”

“ A variable time, dependent upon the season, elapses before the perfect insect makes its appearance, but prior to this occurring, a large circular plate, forming the thorax of the pupa, is thrust off, thus assisting the escape of the fly, which immediately ascends a plant, or other convenient object, to dry and expand its wings (Fig. 1) . In the perfect state it delights to hover in the air, darting away with great rapidity on the approach of any enemies. It also frequently enters houses, where its presence is at once betrayed by a peculiarly shrill noise made while flying. ”

“ The food is chiefly insects but considerable numbers of spiders and daddy-long-legs also are eaten. Beetles, caterpillars, and ants are the larger classes of insect food, but moths, flies, bugs, and a few hymenoptera also are eaten. Among forest enemies that have been found in stomachs of this species are round-headed wood borers, leaf beetles, flea beetles, weevils, bark beetles, leaf hoppers, and jumping plant lice. ”

“ It creeps stealthily along, concealing itself from view as far as possible, and not even the tell-tale glassy surface of the water feels its movements. Measuring its distance well, the [123] larva prepares to seize its prey; in a moment, swifter than the eye can follow, the victim is caught by the apparatus we have described, and in another instant, is in all the agonies of a violent death in the mouth of the larva. So exceedingly cautious are these larvæ in their movements, and so expert and active in darting upon their prey, that it scarcely ever escapes their power. ”

“ In some districts of France it is also very destructive, the grass of large tracts being so completely destroyed by it, that enough food for the maintenance of the cattle is not to be obtained. These larvæ, like the last-named, appear to destroy by eating away the roots of the grass. From these and the foregoing facts, entomology teaches us to regard these two insects, upon which we commonly look with compassion, as occasionally becoming the formidable, though indirect, enemies of man. ”

“ Occasionally this swarming occurs in a house, and, to prevent every corner from being filled with the insects, a fire is built at the orifice of the nest. But they do not hesitate to pass through the fire. While swarming they appear like snowflakes floating about in the air, and it is not uncommon to find dogs, cats, hawks, and almost every kind of bird busily devouring them.
The natives take advantage of the swarming season and collect the ants for food. ”

“ Without their aid it would in many cases be impossible for the agriculturist to hold his own against the ravages of his minute insect foes, whose habits are not sufficiently known to render artificial checks or destroying agents available. The females of all the species are constantly on the alert to discover the proper living food for their own larvae, which are hatched from the eggs they deposit in or on the eggs, larvae or pupae of other insects of all orders, chiefly Lepidoptera, the caterpillars of butterflies and moths being specially attacked (as also are spiders) . ”

“ Its strong and swift flight is sufficient to save it from its enemies when on the wing, but if it were equally conspicuous when at rest it could not long escape extinction, owing to the attacks of the insectivorous birds and reptiles that abound in the tropical forests. ”

“ But though a reduction in the numerical standing of the different species would certainly follow from any increase in the area occupied by the respective individuals, and with even greater certainty would place them in a more secure position as regards their supply of food, yet, when we remember how large a number are dependent upon a supply of insect life for their young, we can understand that it would not alone be a sufficient safeguard against the dangers attendant upon overcrowding. ”