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old man, who now rests in the little sanctuary of St. Peter's at Winchester, would have worked my reformation."
"Heaven grant those prayers may not have been offered in vain," said Humphrey, fervently," and that some chord in your heart may be touched, before the hour comes in which no man can work!"
THE morning was joyous and bright,
But the earth that he was leaving,
For light and free was my heart,
I had yet to bear my part,
In its turmoil and its strife.
But ere half of that day had sped,
It had borne a blight, as it passed,
To the hopes and the promise of spring.
And I thought of the lark I had seen
I wished! oh, I wished, in my heart,
That, like him, I could heavenwards soar; From this earth I would soon depart,
And never return to it more.
And the evening came at last,
And lowering clouds in the west,
As I laid my throbbing head,
And counted the hours that had sped,
F. MALCOLM DOHERTY.
MOST people are aware, as a piece of common-place knowledge, that many animals, before arriving at their mature or adult state, undergo a series of changes in form, of a more or less complete character. To such a series of changes the naturalist applies the term "metamorphosis;" and the study of the disguises which an animal may in this way successively assume, forms one of the most interesting and fascinating subjects that can attract the notice of the general reader.
The great insect-class presents us with the most familiar examples of these changes, and the butterflies and moths exemplify metamorphosis in its most typical aspect. Thus we know that from the egg of the butterfly, deposited by the shortlived parent upon the leaves of plants, a crawling grub-like creature is first developed. This form we name the "larva" or "caterpillar ;" and if we might fail to recognise its relationship to the bright denizen of the air, so far as outward appearance is concerned, we might also be at a loss to reconcile its internal structure with that of the perfect butterfly. Thus the latter is winged; possesses a mouth and digestive system, adapted for the reception and as similation of flower juices; and wholly differs in structure and habits from its worm-like progeny. The caterpillar is provided with a mouth furnished with jaws, and adapted for biting or mastication; its digestive system presents a type differing widely from that of the perfect form; and its crawling, terrestrial habits appear in strong contrast to the ethereal movements of its parent.
The life of this larva may be accurately described as one devoted to its nourishment. Its entire existence, whilst in the caterpillar state, is one long process of continuous eating and devouring. By means of its jaws it nips and destroys the young leaves of plants, much to the gardener's annoyance; and so rapidly does its body increase in size, that the first skin with which its body is provided cracks and bursts, and a process of moulting ensues. From this process the larva emerges, clad in a new skin, adapted to the increased size of its body; and this second skin may similarly become too small to accommodate its ever-increasing growth, and a second process of moulting produces in turn a new investment. In this way the caterpillar may change its coat many times, and on arriving at the close of its larval stage of
existence, may present a very great increase in size, as compared with its dimensions at the beginning of its life.
But, sooner or later, the caterpillar appears to sicken, and to become quiescent. Its former state of activity is exchanged for one of lethargy, from which it awakes to begin an operation of a novel and different nature from those in which it has been previously engaged. It begins to spin-by means of a special apparatus, consisting of glands and an organ, named the spinneret"-a delicate silky thread, with which it invests its body. Within the silken case or 66 cocoon which it thus constructs, the caterpillar body is soon enclosed; the first stage of its existence comes to an end; and the second or cocoon stage, marked by outward quiescence and apparent rest, is known to us as that of the " pupa,' chrysalis," or "nymph."
Although outwardly still, and although all the former activity appears to have been exchanged for an inactive repose, changes of a passive kind, but of marvellous extent, are meanwhile proceeding within the cocoon or pupa-case. The elements of the caterpillar's form are being gradually disintegrated, and are being built up anew in the form and image of the adult butterfly. Old textures are being exchanged for new ones; particle by particle the outward and inward structures of the larva are being replaced by others proper to the mature being; and in due course, and after a longer or shorter period, the cocoon is ruptured, and the perfect form emerges,-a bright and beautiful creature, furnished with wings and active senses, and rejoicing in the exercise of its newborn functious amid the sunlight and flowers.
Such is an outline of the familiar process by which the larva or caterpillar of the butterfly becomes transformed or developed, to form the "imago" or perfect and adult form. And if we review the stages exemplified in the process, we shall be able to detect in each an obvious harmony and correspondence with the preceding and successive stage. Thus we find that the life of the perfect and mature insect is at the best of a comparatively short and transient nature, and its energies are directed chiefly and in greater part to reproduction to the deposition of eggs, from which new individuals will, in due course, be produced. The larval stage, on the contrary, is devoted to nutrition to the laying up, as it were, of a store of nourishment, sufficient to last throughout the lifetime of the being, and to sustain it whilst its adult functions are being performed.
Indeed, the entire lifetime of the higher insect may be divided into, or comprised within, two distinct periods. The first of these latter is the nutritive period, represented by the caterpillar state, when the nutrition of the body is mainly provided for: and the
second period, no less defined than the first, is included in the life of the perfect form, devoted to reproducing the species. This last we might therefore term the reproductive period of insectlife.
All insects, however, do not exemplify metamorphosis in so perfect a manner, as does the butterfly. The beetles, flies, bees, etc., and many other insects, undergo a process of metamorphosis essentially resembling that of the butterfly; the main feature of this form of development being that whilst the caterpillar stage is passed in activity, the pupa or chrysalis is quiescent; and from this resting-pupa the active, winged insect comes forth. The dragonflies, crickets, grasshoppers, bugs, and their allies, undergo, on the other hand, a less perfect series of changes than the foregoing insects. The young grasshopper, on leaving the egg, bears firstly a close resemblance to the perfect insect. It is not of worm-like conformation, and in these two points differs from the larva of the other forms. Then, secondly, it never encloses itself in a cocoon. case, but passes its chrysalis stage in a free and active condition. In this respect it again differs from the butterfly pupa; and its perfect form is attained simply by the development of the wings. So that, in reality, the chief difference between the larva, and the perfect form of the grasshopper, consists in the non-development in the former of the wings, which are thus characteristic of the adult form.
The Dragon-flies illustrate an essentially similar kind of metamorphosis, but also exemplify differences in the details of their development. The Dragon-fly larvæ are active creatures, inhabiting the water of pools; they are of brownish colour, and possess six water legs, and a peculiar apparatus of jaws, consisting of a pair of mandibles attached to a movable, rod-like stem. This apparatus can be folded upon the head, when it gives to the larva the appearance of being masked, and hence the name of "mask" which has been applied to this structure. Or, on the approach of some unwary insect, the jaws can be rapidly extended to seize the unfortunate victim, and convey its to the mouth of it captor.
Having arrived at its pupa-condition, differing from that of the larva, simply in its greater size, and in the meanwhile development of the wings and perfect body within the larval and pupa-skin, the insect at length fixes its body to some water-plant, the pupa-skin splits along the back, and the mature winged insect slowly emerges therefrom. The crumpled wings soon dry harder, and acquire their normal consistency; and the dragon-fly, freed from the trammels of a mundane existence, mounts into the air, and ' revels in the freedom of luxury and light." Tennyson has aptly described this change in his lines :