Swarm (insect)

“ The robin and its sister thrushes and the numerous sparrows attend to the surface of the earth, and aquatic birds extensively destroy those insects whose development takes place either in or on the water.
Not the least among the birds that assist man in his warfare upon insect pests are our beautiful and active warblers that frequent the foliage of tree and shrubs patiently gathering their insect food. ”

“ 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. ”

“ The days lengthen, the breeze has lost its penetrating chilliness, gentle showers descend and water the earth, and there is a general voice heard all over creation,—"Spring has come!" The eggs of a thousand insect species have already perceived its presence, and the newly-awakened beings within hasten to welcome it by bursting from the shell, their long occupied, but now for ever forsaken dwelling-place. Sometimes the young larva bursts through the thin walls of the shell by main force, or eats its way through by means [64] of its jaws, which is occasionally a task of many hours' duration. ”

“ 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. ”

“ Thus massed into a single awl-like beak, the mosquito, without any apparent effort, thrusts them all except the labium into the flesh. Her hind body may be seen tilling with the red blood, until it cries quits, and the insect withdraws its sting and flies sluggishly away. ”

“ 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. ”

“ If he remain standing, the cloud thickens; if he move on, it draws itself out; if he run as quickly as possible, it stretches into a long train, but does not remain behind. If a moderate wind is blowing against them, the insects hasten their flight to make headway against the current of air; [Pg 83] when the wind is more violent all the members of the swarm strain themselves to the utmost so as not to lose their victim, and pounce like pricking hailstones on head and neck. Before he knows, he is covered from head to foot with mosquitoes. ”

“ Let us go back to the swarm of winged males and females that have issued from the nest. The birds are already feeding upon them, for the termites' powers of flight are at best feeble and uncertain. The winds have scattered them, and in a short rime the fluttering horde will be dispersed and probably most of its members will be destroved one way or another. The object of the swarming, however, is the distribution of the insects, and, if a few survive, that is all that will be necessary for the continuance of the race. ”

“ Lured abroad by the mild temperature of the twilight hours, a swarm of insects leave their retreats and come out to play in the open air, to hunt for food, and to mate, one with another. It is then that great night-moths fly abruptly from flower to flower and plunge their long proboscis to the bottom of the corolla, where they suck up the honey; it is then that the mosquito, eager for human blood, sings its war-song in our ears and chooses our tenderest spot for the insertion of its envenomed lancet ”

“ 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. ”

“ These later stages, comprising the greater part of the larval history, are adapted for an inquiline or a parasitic life, where shelter is assured and food abundant, while the short-lived, active condition enables the newly-hatched insect to make its way to the spot favourable for its future development, clinging, for example, in the case of an oil-beetle’s larva, to the hairs of a bee as she flies towards her nest. ”

“ 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. ”

“ 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. ”

“ 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. ”

“ In the end the insects became, owing to this acquisition of wings, and afterwards to the establishment of a complicated metamorphosis, numerically the most successful type of life in existence, the number of species, extinct and living, mounting into the millions.
All aquatic insects are evidently the descendants of terrestrial forms, and the numberless contrivances and temporary larval organs, particularly of dipterous larvæ, are evidently adaptations to the needs of the insect during its aquatic life, and which are cast aside when the creature passes to a different medium. ”

“ 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. ”

“ They do not hop but run along the ground very nimbly after flies and other insects, on which they feed: they likewise feed on small worms, in search of which they are frequently seen to flutter round the husbandman whilst at his plough, and follow the flocks in search of the flies which generally surround them. They frequent the sides of pools, and pick up the insects which swarm on the surface. They seldom perch; their flight is weak and undulating, during which they make a twittering noise. ”

“ 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. ”

“ The hard substances commonly called captain's biscuits are the objects of attack, together with flour, peas, and similar articles of food, and the attacking insect is the larva of the meal-worm, the entomological title of which is Tenebrio molitor. In vain does the ship's cook, with all his art, prepare a soup composed of the richest ingredients, and calculated, as one would think, to gratify the taste of the greatest epicure. The larvæ have been beforehand with him; they have attacked and become mixed with the flour or the peas ”

“ For example (page 2) , the larvæ of certain insects require animal food as soon as they are hatched, and the mother-insect consequently provides them with caterpillars and beetles, by burying them in a cell, side by side with the unhatched larva. But here a difficulty arises: "If the Cerceris were to kill the beetle before placing it in the cell, it would decay, and the young larva, when hatched, would only find a mass of corruption. On the other hand, if the beetle were buried uninjured, in its struggles to escape it would be almost certain to destroy the egg." ”

“ Once such an insect is caught on one of the threads it is lost beyond all hope. There it sticks, struggle as it may. The vibrations caused by its struggles attract the attention of the glow worm which quickly winds up the hanging thread. If it is not hungry at the moment it has been observed to play with its victim, [Pg 5] drawing in and then letting out the line after the manner of a fisherman. Finally the prey is drawn into the silken sheath and entirely devoured, chitinous shell and all. It is not merely sucked, as is the fashion of the spider or the fly. ”

“ 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. ”

“ 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. ”

“ 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. ”

“ 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. ”

“ The creature seemed to crouch ready to spring upon a victim. I wondered at whom or what that death-dealing pike of a snout was aimed. And what did the victim look like? And what were the dimensions of the strange beast or insect of prey? I was soon to learn.
Suddenly the crouching thing hurled itself forward at terrific speed. As it raced on long, slender legs toward the center of the clearing, it appeared in full view to be really an insect. It had three pairs of well-balanced legs that held the segmented body well above the herbage when erect. ”

“ 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. ”