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sending off nerves to each pair of legs, and connected together by commissures running down the length of the body.

The first step of the wasp surgery is to pierce the membrane between the head and first segment of the body and to sting the brain-like supra-oesophagal ganglia of the head, or the commissure cords that connect them with the body in general. This, if we may trust our imperfect human notions of the physiology of the nervous system, is equivalent to the administration of chloroform, as it disconnects the body with the machinery of sensory consciousness.

In higher animals it would produce general paralysis, but not so in caterpillars, every segment having its separate motor centre as above described. The kicking and struggling due to these, although rendered merely automatic, would by the first operation still be inconvenient, therefore this operation is followed by eight others, one perforation and paralysing at each pair of segmental ganglia; thus paralysing each pair of legs and permitting the young wasp to feed upon the caterpillar segment by segment, without inconvenience, either to the feeder or the food which remains alive, though quiescent up to the last morsel, by virtue of its semi-independent segmentation.

There is another species of wasp, to which I have not been introduced by name, which is carnivorous in its adult stage. This feeds on an animal in which the nervous system is more centralised than in the caterpillar, viz., on a grasshopper, the carcass of which is preserved by a single operation that is performed by throwing the grasshopper on its back, bending back its head so as to open the articulation at the neck, and then piercing the membrane and crushing the supra-oesophagal ganglia by a squeeze of powerful jaws. Paralysis and insensibility are thus at once produced without destroying the thoracic and abdominal nervous machinery which controls the functions of respiration and nutrition.

Thus a living but insensible carcass is stored in the larder, one that may be eaten at once or kept in good condition, or even fattened by administering an easily digestible, nutritious syrup that the wasp collects for the purpose; none of its working energy is dissipated in supplying the grasshopper with saltatory or other muscular force; all is economised to do the work of nutrition.

CAT DAY AT THE BRITISH ASSOCIATION."Every dog has his day," in the ordinary course of nature, but at the British Association, September 7th of this year was largely devoted to cats by the Zoological Section, the chief subject being the heredity of their abnormal toes. Mr. E. B. Poulton described a kitten sent to him from Wales in 1879 with six toes on each foot. The mother of this kitten had seven toes on each of the fore feet; thus mother and kitten both had twenty-four toes, though not similarly

distributed.

Then Mr. Poulton's kitten became frequently a mother, her husbands being ordinary twenty-toed cats; nevertheless in many of her families "a high percentage of abnormality occurred."

One kitten with five toes on the fore feet and six on the hind was given to a friend, which "among many families with a high proportion of abnormality, produced a kitten with seven toes on the fore feet and six on the hind, thus reverting to the condition of the great-grand-parent in the possession of Mr. Vaughan" who gave Mr. Poulton his first kitten. This multiplication of toes is still proceeding among the cousins and nephews and nieces, and later generations.

Miss Lydia Becker described a Suffolk cat with abnormal toes, and others joined in the discussion, all agreeing that the phenomena are very interesting, but nobody appears to have suggested the appointment of a cat committee to investigate experimentally and report annually on the subject of such heredity.

Many years ago when I was a boy-there lived in Wardour Street, Soho, a pork butcher named Foot, whose children all had supernumerary toes, and were objects of considerable interest in the neighbourhood. We had an old black servant at the time, and I well remember her explanation. Mr. Foot dealt largely in boiled "pigs' trotters," i.e. feet; these were displayed in the shop window, arranged in a row by Mrs. Foot, who served the customers. Black Polly maintained that the contemplation and handling of so many toes by the mother caused the evolution of her children's abnormality-she expressed her theory, however, in somewhat different terms.

THE HEIGHT OF WAVES.-Some curious ex. aggerations have prevailed concerning this subject, and many have been the controversies relating to it. A captain in the mercantile marine, writing to the "Liverpool Mercury," describes his investigations, which appear to have been carefully conducted by viewing, while rounding Cape Horn, the waves that came up astern from the mainmast in a line of sight to the horizon, and marking on the mast the height of coincidence. On measuring the distance from these marks to the mean draught, he found them to be as follows: 64, 61, 58 and 65 feet in height, and that the length of the waves varied from 750 to 800 feet.

Ansted says: "The highest and largest waves do not often exceed forty feet from the crest to the deepest part of the trough," and adds, "when these great waves approach the shore or shoal water, and reach the bottom of the sea they increase in height, reaching sometimes to upwards of 150 feet, but they diminish in breadth or amplitude, and become pointed."

The difficulty of determining the height of waves from a ship is very considerable owing to the instability of the platform on which the observer stands, while the measurement from the shore is easy enough.

Admitting this, it appears to me that Prof. Ansted refutes himself, as the reconciliation of his two measurements, demands that the shore-breaker shall become nearly four times as high as the deep water wave. This may be refuted by simply standing on a steeply-sloping shore at such an elevation that the crest of the shore-breaker shall coincide visually with the horizon. If such increase of height took place near to the shore it would be unmistakably visible from such a standpoint. If it occurred gradually, say within a mile or two from shore, it would be very distinctly observable by the increased pitching of a ship on approaching the shore.

NOTES ON FASCIATION IN PYRETHRUM.

DURING

URING the past summer the conditions favourable to the development of fasciated growth in plants have been prevalent. Wet, comparatively sunless weather, is highly productive of abnormal growth, and in no class of plants has such growth been more common than in the genus Pyrethrum.

The earliest species to flower is P. roseum and its varieties, the flowers of which are of two classes, single and the so-called double; in the latter the disk florets are large, tubular, and coloured like the ray florets, the former being simply normal flowers with small disk florets.

There has been a great tendency on the part of the so-called double varieties to assume abnormal forms, the most common being a curious ridge-like formation of the receptacle, giving the flower the appearance of a celosia. In the typical varieties, the flower heads were more or less mis-shapen, some very curiously divided across as if they had been cut with a sharp knife when they were unfolding.

In a large collection of plants here very few escaped without some slight trace of fasciation. In July I looked through some thousands of plants at a large hardy plant nursery, and batch after batch of old-established plants, and one year old seedlings showed the same condition, the more highly-developed "doubles " being affected the worst.

P. parthenium has shown the same abnormal condition and growths, but in this species a curious leafy malformation has been developed in place of the flower heads; this growth greatly resembled the huge outgrowths one sometimes sees on common soft herbaceous plants-an excrescence due ofttimes to the development of adventitious buds, and occasionally to arrested growth. The yellow-leaved variety of this species, known in gardens as "golden feather," when allowed to grow naturally, has been equally prolific during the past summer in producing these curious growths; that they are due to the influence of fasciation is proved by the flattened and twisted stem.

P. uliginosum is a late flowering species, with tall,

bold-growing stems, lanceolate leaves and large attractive white flowers. For several years past the plants in the gardens here have shown a strong tendency to produce mis-shapen flowers and stems, the fasciation showing in many instances low down on the stem in the form of a flattened main stem; this flattened condition of the main stem has however not prevented the lateral branches from flowering and producing flower-buds. In this respect it differs from a case noted on p. 50, vol. xxii., where the flattened stem of Tropaolum tuberosum failed to produce perfect flowers, buds only being developed, which were abortive. This autumn it is a matter of difficulty to find a single plant of P. uliginosum without some trace of fasciation; all kinds of monstrosities are to be found, from the shapeless terminal mass of flowers, to a perfect double flower, double in the sense of having two adherent capitulums on one flower stalk.

This excess of abnormal growth in the genus Pyrethrum was due to the wet season. On cultivated ground the effect of so much wet is to present the plants with an overdose of plant-food, rendered soluble by the continuous presence of rain-water. This is very noticeable in the case of P. roseum, a species not so given to abnormal freaks as the last noticed species.

A plant of P. Tchichatchewii (native of Asia Minor), growing in a very dry position under trees, has shown no trace of abnormal growth. This is the only species growing here that has been perfectly free from the influence of fasciation. How far its dry position influenced the growth is a matter for experiment another season. Pinner.

N

JOHN W. ODELL.

L LIFE UNDER A STONE.
ATURAL history is a subject on which, in all

its various branches, many books have been written. Nature, it has often been said, is itself a book; not indeed one that he who runs may read, but a magic volume to those who study it with care. Some pages there are which seem at first sight blank, but these are written in invisible ink, and need only the fire of enthusiasm and the light of understanding to bring out clear and well-defined the message that they bear. Other leaves are inscribed in characters so strange and mystic, that many a sage has studied them in vain, 'until, as time rolls on, there is found at last one wiser than the others, who translates the writing on the page aright. The book of Nature is never finished; daily the great Author adds fresh chapters to the work, yet there is never a dull page, and even those which at a glance may seem least interesting, will always well repay a closer scrutiny.

It is with one of these apparently uninteresting

pages of natural history that we propose to deal-with a chapter called: "Life under a Stone." Now a stone is regarded by most of us without interest; it is used in common parlance as the symbol of all that is worthless, all that is dull, hard, or insensible. Yet, the geologists tell us, the mere pebble rolling at our feet may have a history reaching farther back than the history of man. The tale it may unfold is one to which wise men listen with awe and reverence.

It is not, however, with the stone itself that we have now to do, but with the life beneath it. Shakespeare has told us, in an often-quoted passage, that we may find "sermons in stones," but it was reserved for a writer of our own day to show us that there were also sermons under them.

"Did you never," says Oliver Wendell Holmes, in his "Autocrat of the Breakfast Table," "in walking in the fields, come across a large flat stone, which had lain, nobody knows how long, just where you found it, with the grass forming a little hedge, as it were, all round it, close to its edges-and have you not, in obedience to a kind of feeling that told you it had been lying there long enough, insinuated your stick or your foot, or your fingers under its edge and turned it over as a housewife turns a cake, when she says to herself, 'It's done brown enough by this time'? What an odd revelation, and what an unforeseen and unpleasant surprise to a small community, the very existence of which you had not suspected until the sudden dismay and scattering among its members produced by your turning the old stone over ! Blades of grass flattened down, colourless, matted together as if they had been bleached and ironed; hideous crawling creatures, some of them coleopterous or horny-shelled-turtle-bugs one wants to call them; some of them softer, but cunningly spread out and compressed like Lépine watches (Nature never loses a crack or a crevice, mind you, or a joint in a tavern bedstead, but she always has one of her flatpattern live time-keepers to slide into it); black, glossy crickets, with their long filaments sticking out like the whips of four-horse stage coaches; motionless, slug-like creatures, young larvæ, perhaps more horrible in their pulpy stillness than even in the infernal wriggle of maturity! But no sooner is the stone turned and the wholesome light of day let upon this pressed and blinded community of creeping things, than all of them which enjoy the luxury of legs-and some of them have a good many-rush round wildly, butting each other and everything in their way, and end in a general stampede for underground retreats from the region poisoned by sunshine. Next year you will find the grass growing tall and green where the stone lay; the ground-bird builds her nest where the beetle had his hole; the dandelion and the butter-cup are growing there, and the broad fans of insect-angels open and shut over their golden disks, as the rhythmic waves of blissful consciousness pulsate through their glorified being."

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The description is as graphic as are all wordpictures from the same pen, and the subsequent passage-the sermon "-giving the meaning of the little parable is too pretty to be left unquoted, though it has, perhaps, but little bearing on our subject. "The stone," our author goes on to say, "is ancient error. The grass is human nature borne down and bleached of all its colour by it. The shapes which are found beneath are the crafty beings that thrive in darkness, and the weaker organisms kept helpless by it. He who turns the stone over is whosoever puts the staff of truth to the old lying incubus, no matter whether he do it with a serious face or a laughing one. The next year stands for the coming time. Then shall the nature which had lain blanched and broken rise in its full stature and native hues in the sunshine. Then shall God's minstrels build their nests in the hearts of a new-born humanity. Then shall beauty-Divinity taking outlines and colourlight upon the souls of men, as the butterfly, image of the beatified spirit rising from the dust, soars from the shell that held a poor grub, which would never have found wings had the stone not been lifted."

The living creatures beneath the stone are in the foregoing quotation, perhaps partly to serve the purpose of the allegory, painted in colours somewhat darker than need be, and it will be our task to try and point out that, as there is "good in everything," so there is beauty even in the common-place; and to arouse, if possible, some interest in the life-history (not less curious than that of the hugest mammal) of the tiny beings which constitute this "community of creeping things."

Suppose, then, that during a ramble through wood and field we come upon a stone lying half-buried in the grass or fern which has grown up round it, and turn it over, what kind of creatures shall we find beneath it? The stone may differ according to the district in which it is found; in one place it may be a bit of granite boulder, in another some other sort of stone, but the "little population” under it is always nearly the same. It may vary a little, for instance, if the stone does not lie quite flat, and there are crevices beneath roomy enough to accommodate beetles; we may find some of these hard-coated gentry, but even if the stone seems to lie so close that nothing living could squeeze between it and the ground, yet there will be creatures under it, and one thing we are certain to see, on turning the stone over, is a congregation of woodlice.

Now though the woodlouse is such a common and familiar object, most people know so little of its anatomy as to fall into the error of calling it an "insect." But an insect, to be properly so called, must have neither more nor less than six legs, a body divided into three distinct parts, and must breathe through a system of air-tubes dispersed over the body. The woodlouse clearly does not answer to this description, therefore it is not an insect. To

what tribe, then, does it belong? Many of our readers will doubtless be surprised to learn, that the crawling thing they have always considered as an insect is in reality a crustacean; that is to say, it belongs to the large family of crabs, and is a cousin, though a distant one, of the little creatures whose odd sideway movements in the rock-pools left by the retreating tide are the delight of children at the seaside.

The

At least three species of woodlouse are common in England, yet few people, except naturalists, know how to distinguish them. The first and perhaps most generally known is the "pill-woodlouse," the scientific name of which is Armadillo vulgaris, in allusion to the odd likeness it bears with its hard shelly covering to the armoured quadruped so-named. pill-woodlouse seems really clad in mail, for the horny surface of its carapace has the bluish gleam of steel, and is as polished as a knight's cuirass. Moreover the armour of the woodlouse is even superior, in point of make, to a perfect suit of harness finished by the hand of the most skilled of ancient armourers. For it is so cleverly jointed, that it not only does not interfere in the least with the free movements of its owner, but it actually enables the latter to roll himself into a ball, each segment fitting one into the other and presenting a shining impervious sphere to the attacks of every enemy. Its striking resemblance, when thus coiled up, to a pill, has given to the woodlouse its English name, and it is said that in the earlier days of medicine they were actually used by druggists. How this may be we know not, but certain it is that they have been employed by many a schoolboy in very unpleasant practical jokes.

The second species, the common woodlouse (Porcellio scaber), is devoid of this ability to roll itself up, and this constitutes one of the differences between it and the first-named. The colour is much the same as that of the pill-woodlouse; but it is not nearly so polished, and is sometimes spotted with white. The chief mark, however, by which the two species may be distinguished, is the projection in the common woodlouse of the abdominal appendages beyond the carapace. In the pill-woodlouse these do not appear.

The third species is the land-slater (Oniscus asellus), and this kind also does not roll up. This woodlouse is known by its having eight joints in the antennæ, whereas the others have only seven. It has also two rows of yellow spots, and the same number of white spots along the back. All the species have seven pairs of legs, equally developed.

Woodlice, like other crustaceans, breathe air by gills; but it is essential to their well-being that the air they breathe should be saturated with moisture. Accordingly, they never object to shelter under a stone, otherwise conveniently situated, on the score of its being too damp, though they occasionally prefer, as a refuge, a rotten log, or some other piece

of decaying timber. Damp and darkness are their delight, and the light of day is hateful to them; they will take advantage of any retreat to avoid it. Hence they are sometimes found in the galleried nests of the hill-ant (Formica rufa), where its hosts do not interfere with it, and, indeed, seldom take any notice of this uninvited guest.

Their food is chiefly of a vegetable nature, and as they are very sharp-toothed little creatures, they are rather destructive in gardens, and where they abound it is not easy to get rid of them. Fowls will eat them readily, and when woodlice are too plentiful, the inhabitants of the hen-house may be let loose upon them with great effect; only that in a well-kept garden we are apt on such occasions to find-as the ancient Britons found when they called upon the Romans to fight their battles for them-the invaders more formidable enemies than those they were intended to drive out.

In the order Isopoda, to which woodlice belong, the young are developed within a larval membrane, and when they are liberated by the bursting of the membrane, they nearly resemble the adult, with the exception of having only six pairs of legs instead of seven. The respiratory system is curious. The seat

of the organs of respiration is the lower surface of the abdomen, these organs consisting of leaf-like branchiæ, or gills, protected by plates folding over them.

Woodlice are not by any means the only creatures to be found under stones. Almost as common, perhaps, as these are the millepedes, strange little beings, in appearance something between a hardbodied caterpillar and a centipede. These are sometimes called "wire worms," but quite erroneously, the real wire-worm being the larva of the click-beetle (Elater). Their bodies are perfectly cylindrical; they are generally from an inch to an inch-and-a-half in length, and though they have not really a thousand legs, as their name implies, they have a goodly number, namely, from a hundred and sixty to two hundred. These feet look almost like a fringe of delicate white hairs, and, as the millepede glides along, the movement of its many legs imparts a kind of rhythmic wave-like motion to its whole body, which is pretty to watch.

Three species are common in England. The first, and perhaps best known, is called Julus sabulosus; its colour is dark greyish-brown, with two reddish lines running down the back. The common millepede (Julus terrestris) is the second species, a little smaller than the first, and distinguished from it by lacking the two reddish dorsal lines. The third species (Glomeris marginata) is sometimes called the "pill-millepede," and is even mistaken for the pill-woodlouse, from its habit of rolling itself up spherically. The other millepedes roll themselves also when touched or disturbed, but in a flat spiral, like a coil of wire. The pill-millepede may really

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Fig. 107.-Group of Centipedes-1, Glomeris marginata; 2, Julus terrestris; 3, Polydesmus complanatus; 4, Polyxenes; 5, Geophilus longicornis; 6, Lithobius for ficatus; 7, Scutigera coleoptrata.

restris, and has from seventeen to twenty-one pairs of legs.

The millepedes feed on decaying animal and vegetable substances, and seldom, if ever, attack living vegetation. Thus they are useful as scavengers, clearing away much refuse which would otherwise

In the spring the female millepede sets herself industriously to work to scoop out a hole in the earth, which she intends as a cradle for the reception of her future offspring. When the hole is finished, she makes haste to deposit therein sixty or seventy eggs, which remain about three weeks before they

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