Part 10 (2/2)
The entire edifice has been built around her; she is the hope of the colony, the only mother in this vast a.s.semblage. It is therefore through her that we must look for a past history; and in her we find it.
Some months ago, when she was not more than one thousandth part as large as she is now, though then adult, she migrated from some other city not less populous than this is now. It was just before the periodical rains, when, at the time of the great annual swarming, myriads of winged males and females were evolved from the pupa state, and flew out from their native city. This individual female was found by some of the workers that now compose this colony, and was immediately selected to be at once their prisoner and their queen.
We thus trace our great egg-laying Termes to a city of last year's building, in which for a time she was in an immature condition as a nymph, and before that pa.s.sed a still less-developed stage as a larva.
Hence her life-history goes yet farther back to an egg, originally laid by a former female in exactly the same circ.u.mstances as those in which we find this guarded and immured individual.
Thus we reason; but the female, with her host of attendants, and the house, which is inseparable from their present stage of existence, has been created to-day.
See that creature which with loud ringing hum is whirling round and round the ta.s.sel-like blossoms of this n.o.ble _Eugenia_. You would think it a bird from its ma.s.sive size, but it flashes and sparkles in the sun, like a great jewel. Now it suddenly alights on one of the crimson flowers, and you may perceive that it is a beetle;--a beetle of vast size, and glittering like a lump of burnished metal;--it bears the name of Goliath,--a giant clad in polished armour.
This is his first hour of existence; now for the first time has his nervous system responded to the stimulus of the sweet air and genial suns.h.i.+ne. An hour ago he had no nervous system; no system of any sort; no life; no being; no anything;--he was not until this hour.
Yet if we were to ask a friend conversant with entomology his opinion on the age of this insect, he would immediately give it; not, however, as an opinion, for he would repudiate the uncertainty which such a word implies, but as an indubitable fact, resting on the infallible grounds of constant observation and undeviating experience.
[Ill.u.s.tration: GOLIATH BEETLE, AND PUPA CASE.]
”This fine _Goliathus_,” he would say, ”has not long, probably, emerged from a hollow case of oval form, made of particles of earth agglutinated together by a secretion from the mouth of the larva, and concealed under the surface of the ground. Within that sepulchre it has left its cerements,--the shrivelled skin of the pupa, in which it had been wrapped up motionless like a mummy, for several weeks prior to its appearance as a glittering beetle. The construction of the oval cell was the last act of the larva, a thick, ma.s.sy, heavy-bodied grub, which had fattened for years by feeding on the roots of plants beneath the soil.
Four years pa.s.sed away[69] while yon beetle lay on its side, darkly labouring at this occupation; and before that it was a minute egg for some weeks. The specimen before us cannot be far short of five years old.”
No such thing: the witness is at fault: the _Goliathus_ is not _an hour_ old.
Take notice of the swarm of Gnats, which, like a dim cloud, are uniting in choral dance and song in the beam of the setting sun. Every member of the band that ”winds his shrill horn,” has had an aquatic before he had an aerial existence. A week was spent, in lobster-shape, with two breathing tubes on the summit of his body, in pa.s.sing alternately from the bottom to the top of yonder stagnant pool, and then back from the top to the bottom. And a month was occupied in pretty nearly the same employment, but in another mask,--in fish-like form, with the star-tipped breathing-tube projecting from the side of the tail. But for some months earlier still it was a little lenticular egg, which was agglutinated with a number of others into an oval concave boat, that floated to and fro on the surface of the pool.
And there was something worth observing in that tiny skiff of eggs; for it did, in its artful construction, carry the evidence of time back to a former generation. The eggs individually and separately would have sunk to the bottom of the water; it was, however, essential to their life that they should be in contact with the air as well as with the water.
Hence they were so arranged in the aggregate, that the ma.s.s should swim, though the const.i.tuent individuals could not. To effect this, the parent Gnat, resting on the calm surface of the pool, crossed her two hind legs, and laid an egg perpendicularly in the angle so made: others were added in succession, all maintaining the perpendicular position, all glued together by a cement that resists water, but so arranged, the crossed legs being still the mould, that the outline should be spindle-shaped, while the summits of the central eggs, being a little lower than those of the outer ones, gave a concavity to the boat. So buoyant was it when finished, and the mother's legs withdrawn, that even a drop of water falling full upon it from above, would have failed to submerge it. There it floated, week after week, and month after month, all through the winter, till the genial sun of spring hatched the fish-like larvae to begin their wriggling existence beneath the surface.
Now may we not say with confidence, that the sounding-winged insect looks back to the pupa, the pupa to the larva, the larva to the egg-boat? And more, that the form of the boat,--a form so essential that it could not have lived without it,--looked back to the crossed feet of the mother-gnat, the impress of whose angle its extremities sustained?
Of course we might reason thus: but yet we should be at fault; for the ringing swarm of merry Gnats has been this very evening created.
[Ill.u.s.tration: LARVA OF CASE-FLY.]
The Case-flies (_Phryganea_) that look like delicate moths of sober-brown hue, flitting over the surface of the pond, have, like the Gnats, spent a considerable time under water. When they were larvae, they industriously collected small sh.e.l.ls, fragments of stone, bits of reed, and the like matters, and, connecting them together with strong silk, made out of them slender tubes, in which they sheltered their soft bodies from harm, while their hard polished heads and shoulders projected from the open end. And after having lived through the winter (at least, but I rather think more than _one_ winter) in this state, each closed up the entrance of his castle, by spinning across its open end, a transverse screen of lattice-work, made of very strong and stout silk, which, while it should serve the purpose of keeping out evil-minded intruders, during the helpless inaction of the pupa, should at the same time admit the free ingress and egress of water necessary for its respiration.
The life of the larva, and the exercise of these, its curious instincts, are, together with the duration of the pupa stage, inseparable precedents of the imago state in which we now observe the flying insects. No, not ”inseparable;” for in this case, at least, they had no existence in time; they are prochronic developments.
[Ill.u.s.tration: MELICERTA.]
In this pond at our feet there is an object worthy of a moment's observation, minute though it is, for it is only visible as a speck to the una.s.sisted eye. On one of the whorl-filaments of this tuft of _Myriophyllum_, there stands up a cylindrical tube, firmly adherent to the plant by its foot, but free at its upper end. Small as it is, this chimney is built up of hundreds of pellets, solid, round, and yellow; placed in symmetrical order, and firmly cemented together. What has made this tube? Ha! here is the little architect ready to answer for himself; he thrusts out his head and shoulders from his chimney-top, and announces his scientific cognomen as _Melicerta ringens_.
Look! he is in the very act of building now. Did you see him suddenly bow down his head and lay a brick on the top of the last course? And now he is busy making another brick; his mould is a tiny cup-shaped cavity just below his chin; his material the floating floccose atoms of vegetable refuse. Cilia along his flower-like face collect these atoms into a stream, and pour them into the cup; and cilia within the cup whirl them rapidly round and round in many rotations, until with the aid of mucus they are somewhat consolidated into a round pellet. The brick is made, and nothing remains but that it be deposited next the former, in regular progression, and this is done by the tiny [Greek: tekton], suddenly bending his head forward, and bringing the chin-cup with exact precision to the spot.
And how long has he been engaged in this piece of work? Little more than a day. It was commenced yesterday, when the creature was not more than one-third as large as he is now. But he had lived a few hours before the commencement of his work. He was a rover before he began to be a house-keeper. In that early stage of youth and freedom, before he had made up his mind to settle in life, he had no chin-cup, no flower-like face, and of course no tube. A cylindrical gelatinous pellucid worm, he issued out of the egg, with a brush of cilia on his crown, and danced waywardly through the water. While thus occupied, his form underwent some preliminary modifications, and at length was sufficiently matured, to enable him to choose a spot for the pa.s.sing of his future life, and to commence the building on which he is still engaged.
Not so. The pellet which he deposited when we began to look at him, was the first he had ever made; he had been created but that moment; and all the previous pellets of the case had been called into being just as we saw them. They were built up prochronically.
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