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so voraciously, to the hard chrysalis, fixed immoveably, and sustained without food. The retreat that is chosen, and the préparation that is made for this important change, vary essentially in different species : some retire to the sheltered situations of houses, walls, and other buildings; some bury themselves in the ground; some wrap themselves up in leaves; others attach themselves to the stalks of plants; while others again eat into the stems of vegetables, or the very heart of trees, and there undergo their metamorphosis. Although each kind of caterpillar seeks a different retreat, yet all of the same species seek the same, and adopt the same means of preservation. Were we disposed in this place to enter into, minutiae, we should discover innumerable proofs of design, wisdom, and beneficence in the selection that each species instinctively makes for the place of its abode. Such as are to lie dormant all winter, seek the warmth of our houses, or dig their way into the ground, below the influence of the expected frosts. Such as are to leave their prisons in a few weeks, and before the end of summer, roll themselves up in the leaves of those plants on which they feed. No caterpillar that is to remain in the state of a chrysalis till the following summer, attaches itself to an annual plant; and none that is to enter on its winged state in winter (which some few do) is ever found but upon evergreens. How exact their knowledge, and yet how independeñt of experience or tradition for this office is never performed a second time by the same individual, and no caterpillar ever saw its parents, to derive its information thence.
In the preparation, as we have termed it, which is made for their metamorphosis, caterpillars differ as much as in their selection of a proper place. Some attach themselves by a thread from their tails, and are suspended perpendicularly; while others, among which is the white cabbage butterfly, by another
leave theiubmer, old which
thread across the body, are suspended horizontally. The silk-worm and several others spin a complete covering or case for their bodies, some of finer materials and less agglutinated together than others. ] Some caterpillars form a ball or nest of the mould in which they are buried, glued together by their saliva, and smoothed within; and others fasten two leaves together, or, curling its edges, unite two parts of the same leaf by threads and bands, and thus form a covering and safe retreat for themselves. After the animal has lain dormant its due time in the chrysalis state, the skin or shell bursts, and the perfect insect, in its winged state, creeps out, gradually expands its wings, and, when they are dried, becomes a gay inhabitant of the air. It now no longer seeks to satisfy its hunger on the gross food that it devoured when a caterpillar, but sips the nectar from the blossoms of the flowers'. Having fulfilled the intentions of nature, they deposit their eggs with care, and, having thus provided for a future generation, the insect terminates its short but brilliant career. In the deposition of their eggs, the parent butterflies and moths display wonderful instinct in selecting precisely such places as are best adapted to their future young; such plants, for instance, as will furnish food for the new-born caterpillars, and such parts of plants as are not likely to be removed by decay, or such as will be exactly in the required stage of maturity at the time when the caterpillars are to be born. Thus, a little insect (tinea pomona) lays its eggs in the blossom, that its caterpillar may feed on the fruit of the apple; and several others act in the same provident way. · The papilionaceous insects, in general, soon after their enlargement from the chrysalis, and commonly during their first flight, discharge some drops of a red. coloured fluid, more or less intense in different spe
Dr. Skrimshire's Essays on Natural History, vol. ii, p. 2. .
cies. This circumstance is peculiarly worthy of attention, from the explanation which it affords of what has been sometimes considered, both in antient and modern times, in the light of a prodigy, viz. the descent of red drops from the air, which has been called a shower of blood; an event recorded by several writers, and particularly by Ovid, among the prodigies which took place after the death of the great dictator.
With threat'ning signs the low'ring skies were filled,
And sanguine drops from marky clouds distilled. The purple emperor (papilio iris) is the most beautiful and most interesting of our British butterflies. In his manners, as well as in the varying lustre of his purple plumes, says Mr. Haworth, he possesses the strongest claims to our attention.
It is in the month of July that he makes his appearance in the winged state, and he invariably fixes his throne upon the summit of some lofty oak, from the utmost sprigs of which, in sunny days, he per forms his aërial excursions. In these,' continues this writer, he ascends to a much greater elevation than any insect I have ever seen, sometimes mounting even higher than the eye can follow, especially if he happen to quarrel with another emperor, the monarch of some neighbouring oak. These insects never meet without a battle, flying upward all the while, and combating furiously with each other ; after which they frequently return to the identical sprigs from which they each ascended. The purple emperor commences his aërial movements froki ten till twelve o'clock in the morning, but does not perform his loftiest flights till noon; decreasing them after this hour until he ceases to fly, about four in the afternoon.'
The peacock butterfly (p. Io), whose wings are of a brownish red colour, with black spots, is sufficiently common in the south of England, but extremely rare in the north. The tortoise-shell butterfly · (p. urticu), which appears in its winged state about the month of April, is one of the most common, and at the same time the most beautiful of the British lepidoptera : the upper wings are red, and marked with alternate bands of black and pale orange.
The mazarine blue butterfly (p. cymon) forms fig. 3 in our Frontispiece. I
The sphynges, sometimes called by the title of hawk. moths, are chiefly seen in the evening. The name sphynx is applied to the genus on account of the posture assumed by the laryæ of several of the larger species, which are often seen in an attitude much resembling that of the Egyptian Sphinx,- with the fore-parts elevated, and the rest of the body applied flat to the surface. One of the most elegant insects of this genus is the privet-hawk-moth (sphinx ligustri), measuring nearly four inches and a half, from wing's end to wing's end: the upper wings are of a brown colour, most elegantly varied or shaded with deeper and lighter streaks and patches; the under wings and body are of a fine rose colour, barred with transverse black stripes. The caterpillar, which is very large, is smooth, and of a fine green, with seven oblique purple and white stripes along each side : at the extremity of the body, or top of the last joint, is a horn or process pointing backwards. This beautiful caterpillar is often found in the months of July and August feeding on the privet, the liląc, the poplar, and some other trees, and generally changes to a chrysalis in August or September, retiring for that purpose to a considerable depth beneath the surface of the ground, and, after casting its, skin, continuing during the whole winter in a dormant state, the sphinx emerging from it in the succeeding June. ; Another, perhaps, still more beautiful insect is the sphinx ocellata, or eyed hawk-moth, which is principally found on the willow-tree, in its perfect state, in the month of June: the upper wings and body are
brown, the former finely clouded with different shades, i while the lower wings are of a bright rose-colour, each marked with a black spot.
The largest and most remarkable of the British hawk-moths is the sphynx atropos or death's-head hawk-moth. The upper wings are of a fine dark grey colour, with a few slight variegations of dull orange and white : the under wings are of a bright orange-colour, marked by a pair of transverse black bands: the body is also orange-coloured, with the sides marked by black bars: on the top of the thorax is a very large patch of a most singular appearance, exactly resembling the usual figure of a skull, or death's head, and is of a pale grey, varied with dull ochre colour and black. When in the least disturbed or irritated, this insect emits a stridulous sound, something like the squeaking of a bat or a mouse ; and from this circumstance, as well as from the mark abovementioned, is held in much dread by the vulgar. in several parts of Europe, its appearance being regarded as a kind of ill omen, or harbinger of approaching fate. The caterpillar from which this curious sphinx proceeds, principally found on the potatoe and the jessamine, is, in the highest degree, beautiful, measuring sometimes five inches in length: its colour is a brigbt yellow, and its sides are marked by stripes of a mixed violet and sky-blue colour. It usually changes into a chrysalis in the month of September, and emerges the complete insect in June or July following: some individuals, however, change in July or August, and produce the moth in November. The sphinx atropos is generally considered a very rare insect, and as the caterpillar feeds chiefly by night, concealing itself, during the day, under leaves, &c., it is not often detected. Yet in some years (particularly in the autumn of 1804) it was found in so great abundance in some countries, as to be very prejudicial to the potatoe-plants. . • The alteration of form which the whole of the