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NEW YORK.

LIBRARY

GREGARIOUS SPIDERS.

By G. CADOGAN-MASTERMAN, M.D.

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HE story of the birdslaying spider is so nearly apocryphal that it has all the fascination of the untrue for the popular taste; so, it is almost a pity to spoil the gruesome legend of Madame Merian by the admission that, although the gigantic Mygale does secure sleeping or wounded birds occasionally, they are usually humming birds not half its own size, and they are none of its own trapping, since it does not form a web. This may not be true of every variety, but the spinnerets of all I examined were of quite rudimentary development. And I have seen it come down with so obviously an unintentional and most disconcerted flop on the floor of my quarters that even the almost universal suspensory line was evidently beyond its textile capabilities, or, at least, out of its line of business.

I have sometimes thought that this horrible creature was the avenging Fate of other spiders: that when they became too horribly bloated, too sated with lustful slaughter, it crept upon them in the darksome but never silent night, a living incubus, a hairy, formless horror, and with one stab of its poison fangs recalled the dying agony of an insect hecatomb.

But the still stranger and yet most true story of the gregarious spider of Paraguay is almost unknown. I am far away now from books of reference which might confound me, but I am under the impression that I No. 313.-JANUARY 1891,

told it myself for the first time in England in 1869. The strangeness of it is this: Spiders are the most solitary of assassins, and, were it not for the anatomist, we might believe that they were created without hearts or bowels, for, even the tender passion softens but for a few fleeting moments the cold-blooded ferocity of their lives; many an ardent but too tempting lover amongst them has been at one minute the bridegroom and at the next himself the marriage feast!

I have watched such a swain crouching motionless at the edge of a web for an hour, yet ever ready for a backward spring, stilling-we may imagine-the beating of his vesicular heart lest it should vibrate the threads too aggravatingly, and casting from six to eight sheep's eyes at the velvet-robed damsel within. She, meanwhile, as watchful, almost as motionless, only meditatively twiddling her palpi as she wonders if she love him enough to eat him. And, alas, the next morning I have found his shrivelled remains still in the old spot, but wrapped in the newest of silk and his inamorata the most buxom of Artemisias.

Reaumur hoped to cultivate spider silk: he fed his spinners and spinsters right royally; he sang to them chansons d'amour, but nothing could subdue their longing for arachnidian "long pig"; the big spiders ate the little ones, and then, with unabated appetite, tried to eat each other. A pair of stockings, it is said, was woven from the silk, but I believe are as mythical as the web of Penelope.

Imagine, then, the astonishment with which I saw with my own eyes thousands of large spiders living, working, peacefully feasting together in webs as big as a large table-cloth!

It was on the broad sandy road from the capital to La Trinidad that I met with the first example, and, although it had been much torn by the wind, it was large enough to puzzle me as to its nature. The road is about forty feet wide-road-making in that part of the world means simply clearing a certain space of

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the few trees likely to be in the way and leaving the ground as Nature made it-the palm trunk to which the web was attached at one end stood just within the rough boundary railings, an old mahogany tree stretched its gnarled branches over half the other side for the further moorings, so, about twenty-five feet was its length, its depth six, and it was so far overhead that I could just touch its lower edge with my whip as I rode beneath. Being near mid-day it was untenanted, but the threads were littered with mothwings and other remains of insects, but I noticed that small birds flew through it without hesitation.

From time to time I saw other examples, some larger than the first, but there was ever one point not a little mysterious about them; I had noted in the evening, perhaps, a perfect web crowded with the busy workers; the next day not a trace of it was to be seen! There may have been wind, but in any case one would have expected that some part of its delicate tracery would have been found clinging to the trees; but no-web, spiders, and all had disappeared into the unknown, and it was long before I could trace what had become of them.

During the blockade of Asuncion, however, by the Brazilians, I had a better opportunity than I could have hoped for to study the economy of these strange colonies. I was then living with the United States 'minister in a very large house, having, as is the fashion in that part of the world, an enclosed garden, the patio, in its centre; and there I found to my delight six of these wonderful webs one morning. And with that sublime reasoning we call instinct they were all close to the ground, were moored to it, in fact, by a hundred hawsers. Over the roads they were never less than twelve feet from the ground and, so, must have missed numbers of moths which fly lower, but, then, they permitted horsemen and the high bullock-carts to pass freely beneath.

But this rather forlorn garden was rarely entered except by myself and a stooping crone, the mother of one of the native servants, the usual path was under the shade of the massive piazzas which enclosed it; so the spiders and I examined each other at our mutual leisure and convenience. But they seemed to take very little notice of me, and a double stream would be passing up and down the main cables within three inches of my hand-glass with untroubled indifference.

The spiders seem to belong to the Epeira, but are twice as large as our largest specimens; black, with the exception of a double row of scarlet spots on the sides of the oval abdomen, four eyes (says the imperfect note amongst my rifled papers), but I think it should be, four at the top of the head (cephalo-thorax); two lateral, very strong mandibles, and eight stout, smooth legs nearly an inch in length.

In the centre of the patio was a clump of orange and peach trees-which there reach quite forest sizeand others at a distance of some forty feet: between

these the webs were extended, the majority in the usual horizontal position, but one obliquely, a rhom-boid, with one angle touching the ground. The main. rigging was of stout grey silk, as strong as that with which purses used to be netted, these were crossed at right angles by threads more slender, dividing the surface into squares of about nine inches each, which were filled by a geometrical weblet resembling that spun by our own garden spiders. These did not seem to be regarded as personal property, for the occupants often changed their location, and a double stream was ever passing, as I have said, along the main lines, crawling over or under each other, and never pausing as ants do when they meet for gossip or petty larceny ;. but I noticed that the occupant of the centre of the lesser webs would give it a quick, impatient shake whenever a companion ventured to leave the public gangways: yet I have seen three or four feeding amicably together on the body of a large moth.

As soon as the sun became hot the webs were quite deserted, and the spiders collected in globular masses under the shade of the leaves of the orange trees until evening. But at sunset these crumbled to pieces and the spiders in the most leisurely way dispersed to their aerial fishing grounds. Great numbers. of mosquitoes and other minute insects were caught, but these were brushed away; moths, beetles, and migrating ants-which are temporarily provided with wings-being the chief and most valued prey. I satisfied myself, too, that they did not merely suck. their juices as our spiders do, but ate the whole of the soft parts, which their strong maxillae made easy enough. I many times let them strike their fangsinto any finger, but felt no pain beyond the slight prick of the keen points.

But the oddest trait was that they ate any part of the web which had been torn loose; the nearest spider rolled it up into a ball, moistened it with saliva, and immediately swallowed it. And that explains what becomes of part, if not all, of the old ones.

I was long puzzled by the difficulty, how was the first thread thrown from tree to tree? The spiders were far too solid to float through the air, and as for fastening the line to a branch, descending the trunk, ascending another and dragging the line after them, as the natives assured me they did, that was clearly impossible. But one evening I was fortunate enough to see it done. There was an iron arch over the mouth of the algibe-the Moorish tank-in the patio and at its summit I saw a spider busily weaving a light tangled ball of silk as large as itself, a current of air caught it and it floated away nearly to the top of a tree ten yards away and caught, the spider gave it two or three tugs to be sure of it, and then with the utmost nonchalance crawled away to a height which would be to us as that of St. Paul's, soon came back, was joined by some companions and in less than an hour the bridge was made, and a new web commenced.

THE DAISY'S PEDIGREE.

By A. II. SWINTON.

WO or three years ago," says Mr. Grant

"TWO Allen, in the August number of the

"Cornhill," for the year 1881, "lying in the sunshine on this self-same tangled undercliff, I dissected a daisy for the benefit of those readers who were good enough to favour me with their kind attention. But that was a purely aesthetic dissection, for the sake of discovering what elements of beauty the daisy had got, and why they pleasurably affected our own senses or appealed with power to our higher emotions. To-day, however, I propose to dissect one of these daisies a little more physically and unravel, if I can, the tangled skein of causes which has given it its present shape and size, and colour and arrangement." A very simple and logical explanation of the natural order of things our acquaintance now proffers in respect to this wellfavoured flower on the enchanted precincts of the quiet undercliff, and if lineaments mean aught, then he has most infallibly unfolded its shadowy pedigree. "For," he urges in conclusion, "if we follow down the daisies' descent in the inverse order we shall see that, inasmuch as they have coloured rays, they are superior to all rayless composites; and inasmuch as composites generally have clustered heads, they are superior to all other flowers with separate tubular corollas; while these, again, are superior to those with separate petals; and all petalled flowers are superior to all petalless kinds."

"But," it will be slyly asked by our academic acquaintance, whom we are accustomed to greet of a shiny morning on this self-same landslip, "you are never going to convince me that a fir-tree gave birth to a rose-bush, a rose-bush gave birth to a heather clump, a heather clump gave birth to a waste of eupatory, a waste of eupatory gave birth to a sunflower, and a sunflower gave birth to a daisy." Well, no, not precisely; but to teach the infantile mind we present ideal pictures, confessedly inexact, and it is often possible thus to substantiate that which we cannot demonstrate; and to connive at this same let us leave our sentimental nook for the dutiful arena of golf. We have had a cold unproductive season devoid of novelty, say the insecthunters, and strolling along the craggy shore, when the fires are on in July, as numb as any crab, say, what if we should come upon a pallid, decrepit daisy, with the florets of the disk few, and some of them white and arrested in the very process of turning into those of the ray, just as a sea-anemone would appear were it petrified when in the act of extending its feelers; so that this blossom would thus actually exhibit to our gaze the last two stages of development thought out by the anatomist. Well, everything, it is said, varies on the confines of its possible existence in its present shape, and one is

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here tempted to enquire what changing forces have acted on since the golden morning of the daisyflower, and whose are the viewless fingers that have drawn and pinched out a smart frill around its crown of honeycomb? Nay and what cuts a flag into streamers and spins out a plant into branches and leaves, if it be not the force of the tossing winds and rocking tides? The Jubilee florin falls impressed from the mint, but only think how any daisy crown must have been scourged by the north wind, fluttered by the east wind, breathed upon by the south wind, and kissed by the west wind; and how its fibres variously struck must have vibrated to all the harmony of heaven and composed atomic music until the sun's image was fairly expressed; but let this pass for a more certain fact, since a glance will show the unfinished flower as we plucked it upon the cliff in question, in the very act of unbinding its golden tresses.

Allowing, next, the daisy head to be an example of fasciation, coming true from seed; the latter circumstance being alone curious, since fasciation is far too frequent and identical in the vegetable kingdom to be termed a monstrosity, for only think of the cauliflowers and cockscombs, and all the wilding growths of this description never destined to become species, already chronicled in SCIENCE-GOSSIP ; we hear it likewise asserted that all flowers with separate tubular corollas are superior to those with separate petals. Well, as I recall, on the 17th of September, 1883, as I chanced to be walking along a dark Surrey lane in the neighbourhood of the Green Man tavern, at Worplesdon, I noticed in the bramble-overrun hedgerow the curiously fingered blossom of the Large White Convolvulus (C. sepium, Linn.) now represented by a specimen, which shows how such a bell-shaped flower may revert to a petalate one by dividing down between the veins. Whether the ancestral blooms wore this eccentric passion-flower likeness on this creeper I cannot think, albeit the convolvulus structure assigns to it these five petals; or how these same petals became a white poke, as children call it, I will not say, though this be by some reckoned to have been a freak of nature for which the insects are responsible; and without a doubt insects always enjoy to dive to the bottom of it. Thus much will, however, serve to indicate that not alone have we "still several fish in the very act of changing into amphibians left in a few muddy tropical streams; and several oviparous creatures in the very act of changing into mammals left us in the isolated continent of Australia;" but that we also possess in our own lanes and fields, flowers crystallized in the very act of their metamorphosis; so that not tacitly has evolution "almost always left its footmarks behind it, visibly imprinted upon the carth through all its ages; " but the continuous operation of this law likewise leaves behind it its tags and ends as it weaves the woof and warp of fate. Now it is

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just the recognition of these tags and ends that is wanting to establish the really clever problematical reasoning of Mr. Grant Allen in regard to the daisy's pedigree, as I have little doubt; and if the reader is of my mind, he will acknowledge that the Editor of SCIENCE-GOSSIP in advocating the recognition here of law in place of the byword of monstrosity, applied invariably to that which we do not understand, has thereby cast a flood of light on the past history of the flowers.

There remains a little finishing touch of purple on the flowerets of the daisy resembling the mark of a copying ink pencil, that is apt to attract notice. Were a Grinling Gibbons set to carve a flower-head, it is probable that he would turn it on the wheel, and had he afterwards to colour it he would ask but for few pigments, for robbed of compound hues, pattern and half-tones, the floral colours can be readily suggested, and in point of fact fully-coloured flowers such as dahlias and roses undeniably match well. Perhaps one of the most surprising things to meet with anywhere on this score is a field of roses, where velvety full-coloured blossoms, red, purple, and yellow, spring side by side from the wreck of the things that were; and curiously enough there may be sublimed from the said black mould peacock hues that will surpass the roses themselves in lustre. I allude to the prismatic hues of aniline, first discovered in 1826 by Unverdorben in the products of the dry distillation of indigo, and in 1834, proved by Range to be a constituent of coal tar; and which like aluminium, must be reputed one of the commonest things in the world. Though I have not hitherto obtained great results from staining flower bulbs with prepared aniline dyes, I might yet hint that some of the shale hills that diversify the black country, containing as they do so much of the innocuous raw material, might if ground to powder and mixed with sewage or otherwise, work marvels on the parterres; for after walking some weary miles over them, I can only aver that grass grows on them luxuriantly and ragweed flowers prodigiously, nor will I ever say that it was not a trifle more golden in the sun. Indeed at the present the history of our surprise garden blooms is proverbially far too much of a mystery and too little of a science; for all I could elicit from a professor regarding his educated favourites was, that they were obtained by crossing, but when and where escaped him.

FEW people in England have the slightest idea of the high value attached to scientific education in all the Australian colonies. We have just received a "Prospectus of the Stawell School of Mines, Art, Industry, and Science." This is a well-known Victorian mining town-whose population is not yet commensurate with its public spirit. Whilst we are talking about adopting a Technical Education Act, they are adopting one of their own.

NOTE ON A FOOT-WORKING BLOWPIPE. By H. DURRANT.

A

MONG the portion of our working mineralo

gists there are those who have often felt the want of some method to produce the necessary stream of air for the fusing of the different substances, so as to do away with the blowing through the mouth.

I propose in this short paper to give instructions for making one, which, though rough and simple, is very efficient, which after all is the great desideratum. First of all then, an old square table is wanted, mine is an old machine-stand, which serves the purpose admirably, being very firm; if you have not got a spare table, you can easily make one, providing you do not wish "a thing of beauty,” instead of a working machine; if so, get a carpenter to make the table for you, and so combine the two qualities; though after all it will not be an ornament for the drawing-room. Supposing you have your stand ready, the next thing you will want is a good strong pair of workshop bellows. About four or five inches from the floor, fasten a shelf under the table. Six inches higher fasten a similar shelf. Now take your bellows, lay them lengthwise along the lowest shelf, so that the handles will project beyond the side of the table.

Fasten them in their place; first by a screw through the lower handle into the shelf, and next by a piece of sheet-iron over the nozzle, fasten each side by a screw. Next take a piece of wood, the same width as the handle of the bellows, let it project about three inches over the top bellows-handle; fasten in place by a couple of screws. Underneath it drive a staple ; ditto on top. You will want now about a yard and a half of rubber tubing.

If the tubing was now fastened to the nozzle of the bellows, and the other end to the blowpipe, you would not, by working the bellows, be able to obtain a continuous stream of air, which is what we want ; so we must make an air-chamber, to contain a supply of air while the bellows are being refilled.

For this purpose make a rectangular box about six inches by two and a half. Before nailing the sides up, a piece of thin cloth should be inserted between the joints, to make it air-tight.

The bottom of the box (one of the smaller ends). will have to have a round hole cut in, and a little clack fastened over it, to prevent air from rushing back into bellows when pressure is released.

A hole must also be cut in the top and another in one of the sides. Now get a piece of copper or brass tubing to fit tightly into rubber tubing; fix one end of your rubber tubing tightly round nozzle of bellows, bend the piping round, so that it will come under second shelf, in which a corresponding hole with the one in bottom of box should be cut. Nail your box on over this hole, tightly to the shelf. Now to make

the tube fit air-tight, you must get a cork, cut a

hole through with a sharp knife, making it just a shade smaller than copper tube, fix the cork in the hole of the box underneath, and push in the copper tube, which should be attached to the rubber-tubing. Do the same by the hole in the top of box, inserting cork and copper tube as before, to which must be fastened another piece of rubber tubing, carrying it up under the table, and bringing it through a hole in the front of the table, a little way.

Fix your blowpipe in this tube, inserting a cork if not fitting tightly enough.

The blowpipe can now be made firm by fastening an upright of wood on the top of the table, and fastening the blowpipe to it by bending wire nails round. We have now a hole left in the side of the box.

Now what we want is a bag to contain the supply of air necessary to keep the blow-pipe in full swing.

When you can obtain a nice continuous stream of air, proceed as follows:

Obtain a spiral spring and fit between handles of bellows. Or to the staple tie a piece of cord, bring it to the top of the table, pass it over a small pulley, and attach a heavy weight. Now for the pedal; to the staple on under side of handle of bellows attach another piece of cord and fasten it to the end of a strip of wood, broad enough to place the foot on. You will now find that after you have pressed this with your right foot, on the pressure being relaxed, the bellows will be expanded by the weight attached to the cord.

Of course they are thus filled with air. It will be rather awkward at first to continue the pedalling, but you will soon get used to it, and once you get the bladder filled, a steady continuous motion keeps a nice flame. You can, if you like, weight the

[blocks in formation]

Fig. 1.-Foot-working Blow-pipe. A, bottom shelf; B, top shelf; c, bellows; D, strip of wood nailed on handle of bellows; EE, pulley wheels; F, weight; G, pedal for foot; H, air chamber; K, football bladder; L, blow-pipe; м, upright,of wood; N, hole in table; oo, copper tubing; P, cord.

The bag to produce this must of course collapse by its own elasticity or by weights judiciously placed.

The best and most easily obtainable is a common football bladder. Fix the nozzle over a copper tube and cork it in as you did the other tubes, allowing room for the bladder to expand without coming in contact with sides of box.

You will now find, if you have followed instructions, that if you blow the bellows with your hand, the bladder will fill; once filled, a steady motion with the bellows, never jerky, will keep a constant stream of air issuing from the blowpipe; when the blowing is stopped, a stream of air will continue to flow from pipe till the bladder is exhausted.

If the bladder soon collapses after the blowing is stopped, the wind is escaping somewhere other than through the nozzle of blowpipe. Light a candle and go all round joints, &c., and you will soon find out where. Remedy: stop up with putty or pitch, and do not use the machine again till thoroughly set.

bladder, by tying weights at each end of a cloth, and arranging it nicely over the bladder. This will give you a stronger blast of air, but the pedalling will be much harder, because the bladder empties much more quickly, and also takes more pressure to keep it filled.

Its use

I think there is nothing more to say now. being too well known by mineralogists, &c., except that with care, a flame eight or nine inches long is easily obtainable with a wax candle. All kinds of glassware for naturalists can be made with a very small amount of trouble, such as dipping-tubes, test-tubes, capillary-tubes, tubes for collecting small insects, &c., funnels, and a host of other similar articles, of which I hope to say further in another paper if the Editor can spare me space.

As it is I am afraid I have taken up too much room already, but if any one not quite seeing principle, will write to me (address with Editor), enclosing stamped envelope for reply, I will give further information.

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