CHEATING A SPIDER.-One day last autumn on going into one of the greenhouses, I noticed a fine spider web stretched between the lower part of a wire basket, and some long depending stems of the Ivy Snap Dragon hanging over its sides. A tray of silver sand standing near suggested to me the idea of testing for myself, the different adhesive powers of the concentric and radiating threads of the web. I took a small pinch and from a little distance gently threw it on to the web, which was immediately speckled all over almost as one sees them glistening with dew on an early morning. There was far less sand retained by the radiating threads, than by the concentric ones, but still there was some. Whether my friend the spider recognized the true state of affairs, or imagined the agitation was caused by some unhappy fly, whose intrusion he was prepared to resent, I cannot tell; but at all events, he was down "like a shot" into the centre of the web, and I imagined was somewhat non-plussed at its remaining perfectly motionless; with its anterior pair of legs it then seized two of the radii, and gave the web a good shake. As this elicited no response, it turned, and rapidly retracing its steps, took up its position at the bottom of the flower pot. In a few seconds I treated it to a little more sand, and again almost too quickly to be followed by the eye it was in the centre of the web, and once more made use of the same shaking process to ascertain what was the matter. Four times I threw in the sand, and four times it responded by putting in an appearance, but the fifth time it seemed to have gained wisdom by experience for it would not stir. I waited for a longer interval, and then tried it again, but the fact still seemed fresh upon its memory and it remained in statu quo. By this time the web contained about as much sand as it comfortably could, so as I resolved to try the experiment next day, I thought it would be as well that we should have a fresh web, and so swept away the old one. Next morning on paying my visit I found a first-class web in about the same position, but I could not detect the whereabouts of the spider; however, no sooner had I made advances by an offering of sand, than he took the field as before, prepared to wage an exterminating war with all or any trespassers on his domain. I was called away just then, and when I next visited the place there was no trace of either spider or web. I do not know the specific name of the creature, but it was a small black one of the geometrical kind. I was not aware till I read your last number, that there was any difficulty in cheating a spider, but I firmly believe this one was taken in. I am not in a position to speak positively, and should feel some diffidence in doing so in the face of Professor Rennie and the Rural D.D., but I am of opinion that as the Notonecta will seize the finger, or indeed almost anything if dipped gently in the water, it does so with the idea that it is going to have a meal; and as the deathwatch (be it Anobium or Atropos) will tap several consecutive times at a good imitation of its call (as I have proved on several occasions), I imagine it believes itself answered by one of its own species, and so I believe that the light falling of some grains of sand upon a spider's web produces a vibration so similar to the contact of a fly, that the difference cannot always be recognized by the spider, cunning though he be.-Frederic Henry Ward, Manor House, Poplar. STRIPED HAWK-MOTH.-In the June number of SCIENCE GOSSIP, it is mentioned that a specimen of that rare moth the Striped Hawk (Deilephila Livornica), was found this spring in Ireland. I have also been so fortunate as to obtain a fine specimen of this moth, which was taken at Bredbury, near Stockport, on the 27th of April last, a remarkably early time of the year. It appeared to have just emerged from the chrysalis, and was caught in a garden on a window sill, by a friend who did not know at the time the rarity of the specimen.William P. Marshall. HAIR-WORMS. - The violent thunderstorm accompanied by a deluge of rain, which burst over the metropolis in the early morning of Monday, 3rd June, was followed in the course of a few hours by a curious phenomenon, but rarely observed. The rosebushes and other shrubs in various gardens at Kennington, Brixton, and other southern suburbs, were seen to be swarming with sinall slender hairworms (about 2 or 3 inches long, and not thicker than a lace-pin). These creatures are occasionally found in the earth, but they are parasitic in the bodies of different kinds of insects. A correspondent from the neighbourhood of Carlisle, in a letter also dated 3rd June, informs us that he had found a number of these creatures in his garden, stating that "they come out in quantities in our garden on damp evenings. They are long hairlike-looking worms, from 3 to 4 inches in length, rather pale in colour, and their habit is to wind half of their length round some leaf or stalk, and make a circular sort of motion in the air with the other half." Their history is very obscure, but we believe they are in no wise injurious to plants.-J. O. W., in Gardener's Chronicle. [See also SCIENCE-GOSSIP, for 1865, pp. 107, 197, 288, and 1866, p. 255.] GANNET AND DIVER.-A Gannet was caught alive at Coggeshall, Essex, a short time since, as was also a Black-throated Diver. Both of these birds are considered rare visitors in that neighbourhood. -C. Denny. BOTANY. AN ANCIENT ROSE-TREE.-While very old oaks yews, and chestnuts have each found their "vates" to embalm their memories in the pages of history, there is an humbler member of the vegetable kingdom which has not, so far as I know, found a place in English botanical records. I allude to an exceedingly ancient rose-tree at Hildesheim, in Hanover, which is still flourishing (as a friend of mine, who has lately seen it, tells me), with all the vigour of youth. This remarkable tree (or rather climber, for it is supported against the wall of a church), was in existence when Christianity itself was little more than 1,000 years old; and, if we may believe tradition, had even then been blooming for wellnigh 300 summers! But I will give its history in the words of the well-known botanist, Herr Leunis, himself a resident at Hildesheim. "The oldest known rose-tree in the world is one at present growing against the wall of the cathedral of this town (Hildesheim), remarkable alike for its extreme age, and for the scanty nourishment with which it has supported itself for so many centuries. It varies but slightly from the common Dog-rose (R. canina): the leaves are rather more ovate, the pedicels and lower leaf-surfaces more hairy, the fruit smaller and more globular. The stem is 2 inches thick at its junction with the root, and the whole plant covers some 24 square feet of the wall. Bishop Hezilo, who flourished 1054-1079, took special interest in this rose as being a remarkable monument of the past; and when the cathedral was rebuilt, after being burnt down in 1061, he had it once more trained against the portion of wall which had been spared by the fire. Tradition states that, in the year of grace 814, the Emperor Ludwig the Pious, son of Charlemagne, was staying with his Court at Elze. Being desirous of hunting in the huge forest where now stands Hildesheim, mass was said by the Imperial Chaplain at the place of rendezvous. By some mishap, when the service was concluded and the party dispersed, the vessel containing the sacred elements was left behind. On returning to the spot the following day, great was the surprise of the chaplain to find the holy vessel overshadowed by the tender branchlets of a lovely rose, which had sprung up in the night, and now filled the air with the perfume of its flowers. The Emperor shortly after arrived and by his command a chapel was built, with the altar standing on the spot occupied by the roots of the rose,-that very rose which is now blooming as freshly as though a single decade, and not a thousand years, had passed over its head!" So far tradition. Certain it is that the roots of the existing rose-tree are buried under the altar of the cathedral, and, consequently, are inside the building, the stem being carried through the wall to the outer air by a perforation made expressly for it. My informant tells me that the plant is held in the highest veneration by the inhabitants, and that no one is permitted to gather the flowers or break the branches.-W. W. S. CAREX BUXBAUMII.-Your readers interested in our native plants will be glad to hear that Carex Buxbaumii (Wahl.), Carex canescans (Linn.), still exists near Toome, co. Derry, This rare species is in Britain only found within the compass of a few square yards, and Dr. Dickie, in the "Flora of Ulster," issued a few years since, says, "it is perhaps now lost through the partial drainage of the lake." In the "Cybele Hibernica," published last summer, it is mentioned as gathered in 1855 by the late Mr. Woods. Further, I was informed by the caretaker of the grounds on which the plant is found that, four years since, a gentleman had been there and taken away a specimen of a grass which was not to be had anywhere else. If this meet the eye of the aforesaid botanist, he will learn that his visit is still remembered. On the 1st of June of this year, the Belfast Naturalists' Field Club made an excursion to Toome; and, starting by a train in advance of my fellows, I had a few hours to search for the carex, which, to my great delight, proved to be still occupying the very limited area where Dr. Moore discovered it more than thirty years ago. It is satisfactory to record that the visit of the Belfast Club to Toome did not involve any injury to the Carex Buxbaumii. It is, perhaps, the most elegant of our carices, and its extinction would be a grievous loss to the Irish Flora. The perennial roots were left untouched, and two flowering stems only taken away. One of these now adorns my own herbarium; the other is reserved for my friend, R. Tate, Esq., F.G.S., as a souvenir, reminding him of our joint attempt last summer to find this plant, which attempt only failed for lack of a very necessary element in these pursuits,-time.-S. Alex. Stewart, Belfast. OXLIP. Is there not some mistake about the true Primula elatior (Jacq.) growing on the Mendip Hills? Will it not rather be a caulescent form of the common primrose? I laboured for some time under the delusion that I had the true oxlip in my herbarium, which afterwards proved to be only Primula vulgaris ẞ caulescens. If it is the true oxlip, it will be a very interesting locality.-R. NATURAL HISTORY has been said by some to be a study of facts; by others, a science of observation. Each of these statements is, to a certain extent, truc; it is only by observation that we can acquire a knowledge of the facts upon which all ulterior views must be based.-Rev. Leonard Jenyns, M.A. MICROSCOPY. EXAMINING SOUNDINGS, ETC.-As I was looking through a great many specimens of foraminiferous soundings from the Indian ocean, which I received through the kindness of Mr. Latimer Clark, I felt much inconvenienced by constantly stretching my neck towards the sky in order to examine the objects in a good light with my Coddington lens. Moreover, it took some time and trouble to fix some of the ooze between the two plates of glass. A glass prism happened to lie on the table, and I found that if the object is laid on one side of the same, and Fig. 172. Section of Prism. o indicates the position of the object. which is held horizontally, then the other side will reflect the sky light through the object into the eye in a manner exceedingly pleasant to the observer. In this manner a drop of water may be examined, which will not run off. A rectangular prism I found to be better suited then an equilateral one, and it may be mentioned that the quality of glass being of no consequence, the expense of one is very trifling indeed. I mentioned this application of the prism to several microscopic friends who did not know of it, and I think its publication in the SCIENCEGOSSIP may be a welcome hint to microscopists.C. Becker. MOVEMENT OF DIATOMS.-Mr. Bockett's idea of the nature of the motive power of diatoms is very ingenious; but, as it differs from the opinion I have formed after a long course of observation, I venture to offer a few notes upon the subject. We may take it for granted that a diatom moves by means of organs, acting either upon the water surrounding it, or upon the solid matter over which it glides. That it moves with considerable force is evident from the ease with which it pushes its way through particles of sand, and masses of tangled conferva. To produce this force, any organs acting only upon the water would have to move with considerable velocity, and would cause a commotion in the immediate neighbourhood of the diatom, which would be rendered plainly visible by the agitation of the minute particles floating in the water; but no such disturbance is perceptible. Besides this, the diatom would have the power of moving when suspended in the water, but it appears quite helpless when so situated. We may therefore reasonably conclude that diatoms do not move by means of organs acting upon the water. Of the other known modes of propulsion, there are only two which seem worthy of consideration; the first of these, by means of the protrusion of sarcode or endochrome, so as to form pseudopoda, seems unlikely, from the consideration that if such organs existed, we might reasonably expect that they would be visible in our microscopes; the steady uniform gliding motion of the Navicula seems rather to point to the other form of motive power, the type of which we find in the Gasteropoda; that is to say, in wave-like motions of the so-called foot. It is generally admitted that diatoms have an external layer of soft homogeneous matter, which has to be removed with acids in the process of preparing the valves for mounting. It is possibly in this layer, and in the line of the keel, that the power of motion is situated. I have observed that the Naviculæ always move with their keel pressed against the substance over which they are passing; I have seen them leave the glass slide, and pass over a surface perpendicular to it, and in doing so they have turned over at right angles so as to keep their keel pressed against the new surface; even in this position I have seen nothing of the wave-like motion, but it is quite possible that it may never be seen, for even in a snail it is only visible under exceptional conditions, such as when it is seen crawling over a pane of glass. I have fancied that I have seen a motion of this nature in Bacillarie, and it is difficult to account for the movements of those singular organisms in any other manner, as all who have watched their wonderful military-like manoeuvres will admit. We see what we may call a company slowly stretch itself out into a long single file, then in an instant, as if anticipating a charge from some of the lanceolata about, fall back and form square "with inconceivable rapidity." Now if we suppose that each member of this company has the power of gliding along its neighbour, it is evident that acting simultaneously, no more time will be required for the whole line to draw back than for one of the diatoms to crawl its own length.—F. W. M. WHAT TO DO, AND HOW TO DO IT.-He who would learn the exquisite delights Nature has for those who ardently pursue her, and would acquire a deep sense of reverence and piety in presence of the great and unfathomable mysteries which encompass life, must give his mornings to laborious searchings on the rocks, his afternoons to patient labour with the microscope.-Lewes' "Sea-side Studies." MEDIUM SIZE.-The largest animal known is the Rorqual, which is about 100 feet in length. The smallest is the Twilight Monad, whose dimensions are 12,000th of an inch. It is evident that the middle term is rd of an inch, about the length of the common house fly, which may therefore be considered as an animal of medium size in the creation. -P. H. Gosse. NOTES AND QUERIES. STRUCK BY LIGHTNING.-On Friday, the 7th of June, during a thunderstorm, which passed over Shiere, near Guildford, a man, who was ploughing at the time, and his two horses, were instantaneously killed by the lightning. The tobacco-box and knife which were in the pocket of the deceased ploughman, were rendered magnetic. No mark of any kind was visible on the bodies of man or beast.-E. C. GOLD FISH.-Would any of your correspondents have the kindness to inform me what is the best way of rearing gold fish out of doors? About a fortnight ago I put a few of them into a small pond in my garden, thinking they would there take care of themselves. Two of the number have already died, and a third looks as though he would soon follow. I may mention the pond is about 9 feet by 5 feet, and in depth slopes from 8 inches to 14 inches. The bottom was recently laid with Portland cement. There is a constant change of fresh water, as a jet rises from the centre of the pond, and trickles down from a series of basins. A few worms appear to have crawled in, and there is also a little vegetable débris in the form of leaves and scales, that have blown in lying at the bottom.-G. A. W. GNAT-BITES. - Prevention is better than cure. Upon that principle I advise D. G. to garnish his hat this summer with a bunch of elder flowers. The scent of this blossom is much disliked by the insect in question. When the elder bloom is over, I think that washing the face with elder-flower water before going out, might answer the same purpose. At any rate, I know it is a very soothing application after a bite.-Helen Watney. GNAT-BITES. In reply to "D. G.," I can inform him, that if he rubs the place bitten with a piece of washing soda, or with hartshorn, it will stop the irritation. I used to have a bite trouble me for weeks sometimes, till I tried this. The poison seems to be of an acid nature. Flies, during the summer, are very troublesome, too; but this may be effectually prevented by bruising two or three elder-leaves, and rubbing them over the face and hat. The flies will not settle. In driving, it is a good plan to do the same with the head, &c., of the horse. It saves a deal of misery.-E. T. Scott. MEERSCHAUM." What is meerschaum, and how is it identified when manufactured into pipes ?" asks C. M. in SCIENCE-GOSSIP. The word meerschaum is the German for sea foam, and it is so called from its lightness and white appearance; but it really is a mineral of soft texture, not unlike chalk. It is composed of silica, magnesia, and water. The Turks absolutely employ it as a substitute for soap in washing, for it is quite soft and soap-like when first dug from the earth, and it lathers in water, and will remove grease. When shown at the Exhibition of 1851, the jury came to the conclusion that there was no certain test for distinguishing the true meerschaum from the imitation, but the pipes made of the false are generally heavier and less perfect than those made from the true. There are many blemishes caused by the presence of foreign minerals in the genuine. I am told by smokers that the much-admired yellow colour, which is brought out after long smoking, is produced by the blocks having been kept for some time in a mixture of wax and fat.-Helen Watney. Several varieties are known. 3. Generally associated with hornblendic rocks. 4. It breaks with a fine earthy fracture, that is, like fine-grained chalk. 5. Its hardness is about 2°, or, in other words, it may be scratched with the finger-nail. 6. Its specific gravity is 08, hence it will float in water, and it is from its being picked up at times floating on the sea that the Germans call it "foam of the sea," this being the meaning of the word meerschaum. 7. It has a greasy or soapy feel, in common with most magnesian minerals. 8. When a fractured surface is applied to the tongue it adheres strongly. It is brought principally from Asia Minor, Greece, near Madrid and Toledo, Moravia, and Wermeland. The best tests are those numbered 4, 5, 6, and 7. The above account is that given by Professor Smyth, M.A., in his course of lectures on "Mineralogy," to the students of the Royal School of Mines, Jermyn Street. I may, perhaps, add the pipes are made from the solid mineral, which is steeped in oil or wax, only the inferior articles being made from the compressed scrapings. The specific gravity of it is one of its most distinctive properties. Specimens may be obtained from most dealers in minerals.Archd. Liversedge. THE OXLIP.-I have often found the oxlip growing with the cowslip, both in Wales and Hampshire, but I don't remember ever having seen it growing with the primrose. I have seen it stated that Professor Henslow found the primrose, cowslip, and oxlip, produced from the same root; but the general opinion, I know, is that the Primula elatior is a hybrid between the cowslip and the primrose. The oxlip is of much more vigorous growth than the cowslip, has scentless, pale yellow flowers, and the tube of the corolla is much longer than the calyx. A friend of mine brought in a very fine specimen this spring which he had found growing with cowslips in a field at the back of the lodge.-Helen Watney. SQUIRRELS PERFORATING NUTS. Having had a squirrel in confinement for the last eight months, I can endorse what Mr. Buckle says with regard to their method of breaking open the nutshell before beginning to eat the kernel. My squirrel always bites a little irregular hole in the nut, and then breaks off a portion of the shell sufficiently large to enable him to get at the eatable morsel it contains, which he immediately sets about devouring with great apparent relish. What squirrels when at liberty may do to nuts growing upon trees I do not know.-Helen Watney. TAIL OF LOCUST.-In the Clerical Journal for June, 1866, there is an account of a flight of locusts over Bethlehem; and, in describing one which had dropped, it is said to have had a tail like that of a scorpion. Is there a known variety with such an appendage ?-J. M. P. KILLING COCKROACHES.-In answer to J. G. in your last number, I beg to recommend phosphor paste spread on bread and butter (I dare say almost any eatable would do, but this is what I used), as a remedy for Cockroaches. Some years ago my house swarmed with them, but some ten days (more or less) after this treatment none were to be found. I am told these creatures are cannibals, and I believe it is so; and, if so, the riddance of their presence is easy to be accounted for. While speaking of these unpleasant intruders, I should like to ask if any of your readers have met with intestinal worms in them. I have been working at Cockroaches a little of late, and have found several with these worms in the intestinal canal-all sizes, to of an inch in length; but all the large ones have eggs in them, which generally are extended from the body of the animal as soon as it dies.-W. Hanwell. 10 NEST OF THE HYDROPHILUS.-Should any of your readers be curious on the subject of the nests of water insects, let me recommend them to procure a pair of the large harmless Water-beetle (Hydrophilus Pireus). Yesterday morning I saw Mrs. Hydrophilus cutting up a whole water-plant of a thin grassy kind, and, suspecting her purpose, I removed her with the plant, and a few stray leaves of another, from the aquarium to a separate jar. There, she first made a white silk bag out of materials provided by herself, laid a large number of eggs in it, tied it up, made a basket round it of the water plant, and closed it up with a handle made of another plant, which she painted of a brown colour with her ovi-positor: my children and I watched the whole process-she was far too much absorbed to notice us-the result is a thing looking like a miniature swan! the handle sticking up like the head. Can any of your readers inform us how long her eggs will take to hatch? I have succeeded in hatching the eggs of the water-snail, and can only suppose that on former occasions the contents had been devoured before we removed them.-L. H. F. DEAD BLACK.-Mix lamp or vegetable black with common size, or, what is still better, turpentine. I should think a good instrument for the taking of skeleton-leaves off blotting-paper, and moving from place to place, would be a pair of forceps or tweezers, as used by gold-beaters in laying the gold-leaf on the books.-Geo. Scovell. TO FASTEN DIATOMS.-In reply to E. W. Schoenebeck, respecting fastening the diatoms on the slides, Professor Williamson adds a few drops of gum-water to the last washing, which causes them to adhere to the glass sufficiently to prevent the balsam conveying them away. (See Davies on Mounting, p. 62).-W. Fletcher. DAISY AND BUTTERCUP, BOTH WITH FASCIATED STEMS (G. B. and A. M. M.).-In these specimens it is clear that not only is there flattening, but also a fusion of several flower stalks into one. Moquin Tandon, the great authority on these subjects, considered fasciation as the result simply of the flattening of a single stem.-M. T. M. THE ZOOLOGICAL SOCIETY OF HAMBURG is desirous to obtain living marine animals for the aquarium. Liberal prizes will be given for desirable specimens delivered near London, and collectors are invited to apply in the first instance to Mr. W. A. Lloyd, Zoological Gardens, Hamburg, North Germany. WEATHER-WISE.-In the country the weather predictions which are the most popular next to those of Moore's or Poor Richard's Almanacks depend upon the estimation of trees as thus: If the Oak's before the Ash We may then expect a splash, With the Ash before the Oak We are sure to get a soak. The simple meaning being, that if the leaves of the ash come out before those of the oak we are to expect but a splash or dash of wet for that season; but if the oak take precedence, much wet is to be expected. Now, as I happened to travel from Dorset to London on the 10th of May of the present year, I noticed that while the oak was almost sufficiently leafy to conceal a king, the ash was one uniform bundle of bare twigs; but, strange to say, that this state of things only continued as far as Swindon, as from a little beyond Swindon, and more certainly in the London district the ash was the most forward. Are we, then, from these facts, to predicate a different summer for the west from that of the east; and, if we are not, "Francis Moore, physician," and Old Richard ought to have left us eastern and western weather predictions? Some years there is good reason for gardening and farming according to the behaviour of the leaves of the clm-tree, as thus : When the elmen leaf is as big as a farding, You must sow beans if you aim to have any. But also for this year those who obeyed the first injunction have suffered woefully! Nay, more,even the cautious ones who waited for the penny size have in the west suffered grievously from the frosts of the 22nd, 23rd, and 24th of May, and, indeed, we are all sowing afresh. It remains to be seen how far this kind of almanac will be right as regards barley sowing, the country legend being as follows: When the Elmen leaf is as big as a mouse's ear, When the Elmen leaf is as big as an ox's eye, Then says I, "hi boys, hi! As a rule, barley may safely be sown as soon as the elmbuds burst; but if left until the leaf is nearly grown, it will be usually too late to insure a good crop; but this year some of the earlier sown barleys have suffered like most other things from an unusually severe spring. These remarks may, perhaps, serve to show that it is as difficult to make weather predictions come true by rhyming as it is by reasoning. -J. B. DEAD-BLACK. The dull-black used by opticians for "coating" the insides of microscope and telescope tubes, is a mixture of the best " lamp-black and "lacquer." The former should be well pulverized, adding sufficient of the latter to give it the fluidity of ink. If too much lacquer be present, a "glossy" instead of a 'dead" surface is the result. It may be laid on with a sable brush after shaking the bottle, and the tubes must be heated to insure quick evaporation.-Thomas Curties. STICKING DIATOMS.-In your last number Mr. E. W. Schoenbeck inquires how diatoms may be made to stick on the slides before being mounted in balsam. If he will place a thin film of a very weak solution of gum on the slide, and then deposit the diatoms in it, and allow it to dry, he will find them sufficiently fixed to prevent their being floated out by the balsam.-T. W. G. 3 |