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parent in the water, sinks to the bottom, and remains there till the young insect has acquired sufficient maturity and strength to burst from its confinement. The larva, at first small, increases to nearly half the size of the perfect fly, by changing its skin at different intervals like the caterpillars of moths and butterflies. The appearance of the little cases containing the rudiments of the wings, at the lower margin of the thorax, denotes its change to the state of pupa. The head of this larva is exceedingly singular, being covered with a mask extending over the whole of the fore part of the head, with cavities in · the interior surface to suit the different prominences of the face to which it is fitted with perfect neatness. Its form is triangular, growing smaller towards the þottom: in the latter part there is a knuckle which fits a cavity near the neck, and on this part it turns as on a pivot. The upper part of this mask is divided into two pieces, which the insect can open or close at pleasure, and it can also let down the whole mask, should occasion require. The inner edges of these two pieces are toothed like a saw, and serve the animal as a pair of forceps to seize and retain its prey. This is the general principle on which these projecting forceps are constructed in the larva of the libellalæ; they differ in shape in the several species, but uniformly act in a similar manner. · These animals generally live and feed at the bottom of water, swimming only occasionally. Their motion in the water can scarcely be called swimming; it is accomplished by sudden jerks repeated at intervals. This motion is not occasioned by their legs, which at this time are kept immoveable and close to the body: it is by forcing out a stream of water from the tail that the body is carried forward, as may be easily perceived by placing them in a flat vessel, in which there is only just water enough to cover the bottom. Here the action of the water squirted from their tail will be very visible; it will occasion a
small current, and give a sensible motion to any light bodies that are lying on the surface. This action can only be effected at intervals, because after each ejaculation the insect is obliged to take a fresh supply of water. The larva will sometimes turn its tail above the surface of the water, and force out a smail stream, as from a little fountain, and with considerable force.
Under the same order is comprehended the phryganea, or spring-fly: the caterpillars of this genus live in the water, and are covered with a silken tube. They have a very singular aspect; for, by means of a gluten, they attach to the tubes in which they are inclosed small pieces of wood, sand, gravel, leaves of plants, and not unfrequently live on testaceous animals, all of which they drag along with them. They are very commonly found on the leaves of the water-cress; and, as they are often entirely covered with them, they have the appearance of animated plants. They are in great request among fishermen, by whom they are distinguished by the name of stone or cod-bait. The fly, or perfect insect, frequents running waters, in which the females deposit their eggs.
To their delicious task the fervent bees
The hymenoptera have four wings, but not fibrous like the former order. They generally possess a
sting or piercer, which in some is innocent; but in others, it is calculated for the discharge of a highly acrimonious or poisonous juice, as in wasps and bees. The genera are:-1. Vespa, wasp, hornet 2. Apis, bee..-3. Formica, ant.-4. Terines, white ant:-5. Ichneumon, &c.
Many of the wasp kind, like the bees, live in society, make combs in which the females deposit their eggs, and feed their caterpillars with an inferior species of honey. Others of them construct a separate nest for each individual. There is a species of sphex called the ichneumon wasp, whose manner of constructing its vest is extremely curious. This little creature generally begins its work in May, and continues its labours through the greater part of June. The object of her labour seems at first to be the digging of a hole a few inches deep in the ground, in the construction of which she forms however a hollow tube above ground, the base of which is the opening of the hole, and which it raises as high above ground as the hole is deep below; it is formed with great care, resembling a coarse kind of filagree work, consisting of the sand drawn from the hole. The sand out of which she excavates her cell is nearly as hard as a common stone. This it readily softens with a penetrating liquor, with which she is well provided; a drop or two of it is imbibed immediately by the sand on which it falls, which is instantly rendered so soft, that she can separate and knead it with her jaws and fore feet, forming it into a small ball, which she places on the edge of the hole as the foundation stone of the pillar she is about to erect; the whole of it is formed of such balls, ranged circularly, and then placed one above the other. She leaves her work at intervals, probably in order to renew her stock of that liquor which is so necessary for her operations : these intervals are of short duration ; she soon returns to her work, and labours with so much activity and ardour, that in a few hours she
will dig a hole two or three inches deep, and raise a hollow pillar two inches high. After the column bas been raised to a certain height perpendicularly from the hole, it begins to curve a little, which curvaturo increases till it is finished, though the cylindrical form is preserved. She constructs several of these holes, all of the same form and for the same purpose. It is evident the hole was dug in the ground to receive the egg, but the purpose of the tube of sand is not very apparent. By attending to the labours of the wasp, one end, however, may be discovered ; it will be found to serve the purpose of a scaffold, and that the balls are as useful to the wasp as materials to the builder, and are therefore placed as much within her reach as possible. She uses it to stop and fill up the hole after she has deposited an egg in the cell, so that the pillar is then destroyed, and not the least remains left in the nest. The parent insect generally leaves ten or twelve worms as provisions for the young larva. In all these fabrications there is a degree of ingenuity in design, and exactness of execution, which, independently of the labour required in their construction, excites our admiration. The talent, if it may be so expressed, of the insect race, is more obviously displayed in the formation of the dwellings than in most other particulars of their history
The bee is an insect too well known to require a particular description. The males have no sting; but the females, and the drones or neuters, have a very sharp pointed sting concealed in their abdomen. The female of the honey bee is much larger than the male, or the neuter; her feelers contain fif. teen articulations; and her abdomen, composed of seven segments, is much longer than her wings.
'See a further account of wasps'-nests in Time's Telescope for 1815, p. 193; and some atacreontic lipes to a wasp in T, T. for 1817, p. 245.
The feelers of the male contain only eleven articulations. The neuters are much smaller than the males or females, and their feelers consist of fifteen articulations,'. .
Strength in her limbs, and on her wiog dispatch,
CHURCHILL. · Sir Richard Blackmore, whose poem of the Creation' has been for many years most unjustly neglected, gives this fine description of the economy of the bee :
What various wonders may observers see
Their rooms, and in the dark their lodgings rear !
1 For further particulars concerning this curious insect, as well as numerous poetical illustrations, we refer to Time's Telescope for 1814, pp. 72, 73, 271, 274; for 1815, pp. 112, 115; for 1816, pp. 149-151, 152; for 1817, pp. 82-84, 118, 149-151, 181, 216, 241, 303; for 1818, p. 72; for 1819, p. 84; and in the present volume, pp. 147, 191. .