Réaumur says he often, in the month of May, on looking at his rose-trees, detected these insects at their work; all he had to do was, to stand and patiently watch by the side of a tree, the leaves of which exhibited the singular marks made by this insect. Many times have the same appearances arrested our attention, and without doubt that of the reader. The spectacle of insect ingenuity which it affords well promises to repay a little exertion in endeavouring to find out the nest to which the pieces are conveyed, and some neighbouring post or footpath will probably discover it to us after a sharp scrutiny. Sometimes the insect makes a bad choice of a leaf; it may be, perhaps, too tough for her; but she soon discovers her mistake, and leaves it, half cut, to seek a better on the same branch.
A Rose-branch cut by the Bee.
The nest formed by a species of moth for depositing her eggs in, is one equally interesting to describe. From the resemblance of her actions to the well-known account of those of the eider-duck, whose maternal love strips her breast of down for the purpose of protecting her eggs, we might almost venture to call this moth the eider-moth, were it not that it is known under another and far less appropriate name—the gipsy-moth. Indeed, in the care of the insect the mother's love is, as we might say, even more powerful than in the bird; for, while the latter has the pride and pleasure of seeing her little ones grow up around her, the poor insect, after stripping herself of her own soft, warm down, thus testifying her love to her offspring even to death, presently expires. The insect in forming her nest first plucks off, by means of a singular instrument, like a pair of tweezers, with which she is provided, a little portion of down from her body; seated upon a tree, she attaches this to its trunk, and then deposits an egg in it, which immediately adheres to the down, and becomes coated with it. The remainder of her operations, until she has deposited the entire number of eggs, are but repetitions of the same actions. When the process is at an end, she begins to form a regular tile or covering to her nest, and this she effects with a degree of skill not unworthy of the most consummate thatcher. She arranges the hairs of the down just as the thatcher does his stems of straw for the cottage roof, so that they all slope downwards, resembling much the smooth pile of a hat. By this arrangement of the down, it is next to impossible that in the most drenching shower the eggs, warmly wrapped up within, should be wetted or otherwise injured, and the down itself, being a material which, as we all know, is a non-conductor, preserves the eggs from the influence of the most severe frosts. In shape, this nest of eggs resembles a skittle, or a truncated cone, the broad end downwards. The engraving represents this form, and also shows the insect at work constructing the nest.
The Nest of the Gipsy-moth.
Eggs of Lackey-moth. (Natural size, and magnified.)
Let us now pass on, to mention, that many eggs are deposited without any special protection of the kind we have described, and without what would be with propriety termed a nest. A moth, called the lackey-moth, frequently ornaments the young twigs of trees in our gardens with exquisite bracelets of glistening white eggs, looking like beads. From two to three hundred of these eggs are glued on by the insect around the twig, by means of a tenacious waterproof cement, and are arranged with an accuracy of the most marvellous character, in a close spiral line upon the twig. The cement employed by the insect in uniting her eggs, and in varnishing them over, is so hard as to serve the purpose of a covering, which admirably casts off the rain, and preserves the eggs free from injury by the elements all the winter long. Many eggs are simply glued on irregularly upon the stems and leaves of plants, their shells or outer coating, together with the protecting varnish, being sufficient to preserve them from the inclemencies of the weather; but some are piled together with the most striking regularity, in regular columns of eggs.
In addition to these, it is proper to state, that some insects lay their eggs in the body of the young of others. Of these, those which are most dreaded by the insect tribe are the little but terrible flies, called Ichneumons. They are so called because in their actions they agree with the popular account of those of the ichneumons of Egypt, which were venerated as the destroyers of the eggs of serpents and crocodiles. "Such," say Messrs. Kirby and Spence, "is the activity and address of the ichneumons, that scarcely any concealment, except perhaps the waters, can secure their prey from them; and neither bulk, courage, nor ferocity, avail to terrify them from effecting their purpose. They attack the ruthless spider in his toils; they discover the retreat of the little bee, that for safety bores deep into timber; and though its enemy, the ichneumon, cannot enter its cell, by means of her long ovipositor (organ for depositing the egg), she reaches the helpless grub, which its parent vainly thought secured from every foe, and deposits in it an egg, which produces a larva that destroys it. In vain does the destructive cecidomia of the wheat conceal its larvæ within the glumes that so closely cover the grain; three species of these minute benefactors of our race, sent in mercy by Heaven, know how to introduce their eggs into them, thus preventing the mischief they would otherwise occasion, and saving mankind from the horrors of famine. In vain, also, the cynips, by its magic touch, produces the curious excrescences on various trees and plants, called gulls, for the nutriment and defence of its progeny. This parasite insect discovers its secret chamber, pierces its wall, however thick, and commits the destroying egg to its offspring." In vain, also, might we add, does the sand-wasp excavate her deep cell for her young ones; for when once the ichneumon has discovered the retreat, the destruction of the young larvæ is inevitable. She pierces through the defences piled over the mouth of the cavity, with all the precision and patience of a higher creature, and rests not until she has thrust down her long ovipositor, and placed the egg in the body of the helpless prisoner below, when she flies away, confident that the days of her victim are numbered, and having thus doomed him to be eaten up alive! The common caterpillar, which, by its ravages in our cabbage rows, makes itself a little too familiar to us, has a fierce enemy in these flies; they dart upon it, pierce its body in many places, laying an egg in each wound; these in due time become hatched, and eat their way out of the body of the poor caterpillar, who soon dies, while the larvæ, after undergoing their proper transformations, become perfect insects themselves, fully equipped to proceed to the same work in some other individual of the caterpillar kind.