Three Hundred Things a Bright Boy Can Do

CHAPTER XI

Chapter 115,507 wordsPublic domain

BUTTERFLIES AND MOTHS

For those boys who have the good fortune to live in Britain, few hobbies are better or more enticing than collecting butterflies and moths.

The following apparatus will be enough to start with: (1) a butterfly net; (2) a few dozens of one ounce and two ounce deep willow pill-boxes, which may be strengthened by a little liquid shellac glue run round the inside edges; (3) a handbag which excludes the light; (4) a two-pound biscuit-tin with tightly-fitting lid; (5) a zinc pinning box, cork lined; (6) some entomological pins in three sizes; (7) some setting boards or blocks; and (8) a store box for keeping the specimens when dry enough to remove from the setting boards. We will now consider these items in detail.

The butterfly net can quite easily be home-made, though, where money is plentiful, it is best bought with the other things above named. To make the net-frame, obtain from a dealer what is called a Y-piece, in brass tube. Then obtain a piece of short walking-stick, not more than two feet long, which will fit into the lower section of the Y, which has a broader tube than the two upper sections. A short stick is always best, because more handy and sure in manipulation when catching the butterflies. Into the upper sections of the Y place the ends of a piece of cane about three or four feet long, being careful that each end of the cane fits tightly into the brass sockets. Then get a lady friend to make for you a green or white leno-muslin bag net, with a brown calico hem attached, into which the cane runs. This net should be made just deep enough to reach with the hand to the bottom, or an inch or so deeper only. Mind the bottom is made round, and not jelly-bag shaped with a point, which will ruin nearly all your captures before they are secured. Before using the net, have the muslin steeped in water for a whole night, so as to take all the stiffness out of the muslin. It will require several rinsings before the size is all removed, and it becomes quite soft. Never mind the loss of colour if green--it will only look the more workman-like. In using the net to catch the specimens, like so many other things, it requires practice to make perfect; but when once the knack is obtained, it should be a rare thing to miss a specimen. Don't race after them, but wait until the butterfly hovers over a flower, or flies steadily past, then, with a bold, steady stroke, catch it in the centre of the net opening, at the same moment giving the wrist a sharp half-turn, which will close the mouth of the net, and so secure the novelty.

Carry the empty pill-boxes in the right-hand side pocket of the coat, transferring them to the left-hand side as filled, so that the full and empty boxes never get mixed in the pockets. Having safely netted the butterfly, place the net on the ground, and take a suitable sized pill-box in the right hand. Remove the lid, which is to be placed in the ball of the hand loosely under the bottom of the pill-box. This leaves the left hand free. Then insert the right hand into the net, and cover the butterfly with the pill-box, holding it with the left hand from the outside of the net, carefully keeping the gauze tightly over the box with the left forefinger. The right hand, which is now free, still contains the lid of the pill-box, which gently place over the butterfly, slowly drawing out the gauze remaining between the lid and the box. Quickly transfer the filled box, which should contain _only one_ specimen, into the dark left-hand pocket. Most butterflies will at once become quiet in the dark, if it is not too hot. As opportunity occurs, it is best to transfer them to the hand-bag, which should be left near, under the shade of a bush in a cool place. By this means every specimen should be so boxed without the apparent loss of a single scale from their wings. Only take good specimens--don't be tempted to get a quantity, but rather go in for fine quality. Especially avoid any which are chipped, rubbed, or otherwise unfit for cabinet specimens. It is a great mistake to take imperfect specimens, for they give just as much trouble as the finest, and are never of use either for the collection or for scientific purposes. If it is not convenient on arrival home to immediately set out our captures, they should not be killed, but placed in the biscuit-tin or left in the bag just as they are, in a cold, dark cellar, or like place, where they will be all right for a couple of days or more, remaining perfectly still.

Having brought home our captures we now produce the biscuit-tin. This is to be used for the "lethal-chamber," where the specimens are to be sent to sleep, but not to "awake refreshed." The processes of by-gone times for killing butterflies for collections have been many, the most primitive, perhaps, being pinching the under side of the thorax, or that part of the body to which the wings are attached. Doubtless, there are in the various collections of butterflies, large numbers of fine specimens which have been so killed; but it is an objectionable plan, because even when skilfully executed, the specimens are more or less mutilated in the structure, and are consequently difficult to set out with accuracy. We are almost certain by this method to break off a leg or two, or otherwise render the specimen imperfect. Chloroform is used by some people to kill their butterflies, but it is unsatisfactory, for it often renders them very rigid and too stiff to immediately set out, which is a great disadvantage. Much the same may be said of the fumes of cyanide of potassium, which constitute the active properties of the "killing bottles" sold by the dealers. It is, however, always wise to keep one of these bottles in the hand-bag, in case something very special is to be immediately stupefied. It must, however, be a good large bottle, with wide mouth, for it is needed generally for the big butterflies, such as the larger fritillaries, purple emperors, and the like in size and strength. There is nothing, however, so good for obtaining perfect specimens as boxing the butterflies in the nets, conveying them home in a dark hand-bag, and then killing them in a biscuit-tin with the fumes of _strong_ liquid ammonia. It is best to buy a four-ounce tightly-stoppered squat-bottle for keeping the ammonia, which, when not in use, should be placed out of the light, in a drawer or cupboard, taking care the stopper is tightly fixed. In buying the ammonia ask the chemist for that with a specific gravity of .880, which is commonly kept by them. Some chemists will try to persuade the buyer that it is not safe, so as to supply a weaker article; in which case don't trade with him again, for anything weaker will not only not kill the butterflies, but simply irritate them into knocking themselves into small pieces. Now to proceed. We place about a large teaspoonful of the liquid ammonia into a little cup, or better, in a small mustard-tin lid, taking care to keep our eyes and nose clear of the fumes. Place this as quickly as possible at the bottom of the biscuit-tin, and over it loosely a piece of paper, so as to let out the fumes, but to stop the pill-boxes from falling into the fluid, and so doing damage to box and contents. Then place the boxes containing the butterflies into the tin and tightly close the lid and leave them for not less than half an hour, or better still, a little longer. The boxes thus placed may be left overnight and opened next morning, if more convenient; but in that case it is best to put in with them a small piece of damp sponge about the size of a walnut, so as to keep the specimens from getting too dry. This damp atmosphere should also be there when the butterflies are stored away alive in the dark, for a day or two, as described already.

On opening the lid of the biscuit-tin containing the ammonia and pill-boxes, be careful to keep your face well away, or the puff of vapour may be very painful. There is no danger whatever to be feared from the use of ammonia in this manner, but still it may lead to temporary discomfort, such as pain in the eyes and loss of breath for a moment.

Having removed the lid proceed in the following manner: First place on the table before you a sheet of white paper or a blotting-pad. By your side on the table have a small tea-tray, or other flat receptacle. Take out of the tin one of the top pill-boxes, open the lid, and shake out the butterfly on the sheet of paper in front of you. Then put the lid of the pill-box with its top turned downwards, on the tea-tray, and place the remainder of the pill-box, _sideways_ within the lid. The object is to let the air get to the inside of the boxes, so as to evaporate the ammonia still remaining about them, or the next butterfly to occupy the box will object to the stale fumes of "smelling salts," and probably knock itself about in consequence. The boxes may be thus all emptied and left to air, which will not require much more than an hour, or even less, if the tray be placed in the sunshine near an open window. By placing each box sideways in its lid, the boxes and lids all fit one another, and do not get tiresomely mixed.

In shaking out the butterflies place them in rows neatly on the paper, so that you know which was the first to leave the boxes, for that row should be the first pinned, having been exposed longer to the fresh air, to permit the ammonia attached to them to evaporate. If pinned too soon, the ammonia is apt to affect the metal of the pin and make it brittle where it passes through the body of the insect. The action of this gas is most peculiar on the colours of some insects, especially on that of the small heath butterfly, marbled whites, or some of the blues. When seen for the first time one is horror-stricken, and apt to exclaim that the specimens are ruined with the nasty stuff. This, however, soon all passes away as the ammonia evaporates and the normal colours reappear in all their former beauty. Some collectors rail against ammonia, using themselves some worse killing medium. There is no other such medium which will allow of one, after pinning the insect, to move it up and down quickly in the air with the effect that the wings are as flaccid as though the specimen were alive. It leaves not the slightest trace of rigidity, which is of the highest importance for quick and successful setting out.

The next proceeding is one which requires delicate handling and touch, which can only come with practice. It is pinning the insects. To do this there is only one way which permits of the specimen being afterwards exactly set out, and that is, the "proper way." Any deviation from it, simple as it is, leads to all sorts of trouble and vexation when we come to set the butterflies out on the blocks. Take the butterfly--with the wings closed together over the back, so that the under side only can be seen--between the left hand first finger and thumb. Touch it deftly, but firmly, holding no more than is necessary of the under side of the thorax, where the legs are fixed. Be very careful not to break off any of the legs, or rub off any scales from the body or legs. A small pair of curved forceps are of great use in delicately placing the butterfly in position between the fingers. The proper position allows of the wings to more than half open, when gently blown upon with one's breath. Then choose a pin of suitable size, rather a little large than otherwise, and pass it through the centre of the upper part of the thorax, just where the two front wings meet. Mind it is exactly in the centre and so placed that the pin's head leans somewhat forward when the pin is fully in the body. Pass the pin well through the body, so that at least one third of its length is clear of the underside of the butterfly, and all as nearly as possible the same distance through.

When we have pinned the specimens, we proceed to set or spread them out on the blocks to dry. In selecting these, say they are for butterflies, do not get the slot groove down the centre too wide, as is needed for the fat-bodied moths. Those blocks used in this country are generally somewhat rounded on each side where the wings are to rest. This is called "round-setting" in distinction to "flat-setting," which means that the wings, when quite dry, remain set out flatly at right angles from the body; while round-setting leaves them drooping at the tips in an unnatural manner. Round-setting is considered, outside the British Islands, an insular abomination. It was the style, unfortunately, adopted in this country with the dawn of the present activity among British entomologists, and everybody knows how difficult it is to change even such a simple fashion as the round-setting of butterflies. Simple as the matter seems at first sight, it has contributed more than any other cause to the generally shameful ignorance which prevails among British entomologists of even the butterflies of the Continent of Europe outside our islands. Because they can only be obtained from abroad "flat-set," most of our collectors would hardly look at a "foreign" butterfly; and so the study of the British species has been blocked for years, entirely from this cause, which fostered so largely the prejudice in favour of "British specimens." A "British" Camberwell Beauty is now worth a sovereign, if taken in Britain, although it doubtless flew over from the opposite Continent; but the same specimen, if taken in France or Belgium, would not be worth sixpence to a British collector. Now all this is wrong and should not be. Of course, it is quite right to know what does occur in our country, but there is no need for these absurd differences in value of the specimens, whether taken in Britain or on the mainland of Europe. It leads to fraud, and it is sad to think that some professional dealers have actually made more than comfortable livings, chiefly by inducing young or inexperienced people to pay long prices for "British" specimens which were perhaps captured in Germany, where they were set on rounded blocks, sent out for the purpose to deceive English people, because they were "round-set" and pinned with Birmingham-made pins!

Another result of this insular prejudice is that some species of butterflies very closely allied to others have been overlooked for want of familiarity with another Continental species. A case of this kind was the cause of our last addition to the British list being so long overlooked. There was this butterfly, quite common, year after year, within twenty miles of London, and flying over fifty miles of country, overlooked; all because of our want of knowledge of even the commonest European species.

We therefore recommend the flat-setting, and if the new generation of students of butterflies will adopt it, the round-setting style will disappear in a very few years.

The blocks should be covered with very fine cork, or may be of soft wood, if the steel pins can be obtained. Then they would be cheaper, as the cork covering adds much to the expense, besides being always unsatisfactory, in consequence of the holes in the cork, which hold mites and such vermin.

Place the setting block on the table, with the top furthest away from you. Proceed to select the various butterflies from your damp collecting-box which will best suit the size of the block, allowing about a quarter of an inch clear from the outer edge on each side. Then, with the forceps, take hold of the upper part of the pin near to the body and firmly drive it in the same leaning position as it is fixed into the body, firmly into the _exact centre_ of the groove. If the pin will not go readily into the block, make a lead for it with a sharp-pointed penknife. Do not be tempted to push down the body on the pin, or your specimens will, on removal from the blocks, be all sorts of heights on the pins, and quite unfit for cabinet purposes. Next see that the shoulders of the wings just touch the edge of the block, so as to place the wings flat, without tilting up the tips. Observe carefully that the bodies are straight and lifted by placing under them bits of paper or cotton wool so as to extend on an even plane with the thorax and wings. Continue placing your specimens until exhausted in number, or until the block is quite full, after leaving a clear space between each butterfly sufficient to lift the wing tips slightly forward of the front part of the head. Then with a sharp penknife, very neatly cut a thin nick in the under edge of the ends of the block directly below the shoulder piece of the centre groove. There should be four of these little nicks. Next get a piece of _glazed_ cotton thread, and tie a knot at one end. Insert this knot in the top left-hand nick, the knotted end being below the block. Very gently, but firmly, bring the thread over the end of the block, close to the shoulder, down the left-hand side closely into the inner edge of the block, catching it in the bottom left-hand nick under the block. This will have had the effect of placing all the wings firmly on that side of the block. Then carry the thread underneath the block into the top right-hand nick and over the end of the block, down the right-hand upper side, over the lower end, firmly fix in that nick and cut off the thread. Great care must be taken to pull the thread over the wings not so tightly as to mark them. A good plan is to push under each upper end of the thread a thin pin which eases it, so as to avoid damaging the top and bottom specimens in the row while setting them into their respective places. These pins may afterwards be withdrawn. Next proceed with a very fine pointed needle to gently lift all the wings into their proper places so as to get the effect of "a well-set butterfly."

It may be found that the thread is too slack in places to hold down the wings in proper position. That may be obviated by neatly cross-pinning down the thread on either side at intervals between the butterflies.

When all the specimens have been arranged with perfect uniformity, take two slips of tracing-paper, which have been previously cut to fit the length of the block, and each must be three-fourths the breadth of one side of the setting block. Then lay one of these strips of paper on the left-hand side, being very careful to keep just clear of the thread. All the wings will be seen plainly through the transparent paper and can be readjusted if any slip out of position. Next place with the forceps a No. 10 entomological pin firmly through the top and at the bottom of the paper, near the edge next the cotton. Place another between the first and second butterfly on the block, and so on down the row; also, _as you go along_, place another pin between the outer indentation where the upper and lower wings meet; also put a fourth pin by the tip of the upper wing. These pins should firmly secure the paper over the wings, which, when thus treated on both sides, will dry into the desired position for cabinet specimens. The greatest care must be taken not to allow any pin-point to enter the wing or fringe of a butterfly, or it will be quite spoiled. Next very carefully and gently undo the fastened thread, first taking out any cross pins which secure it. After its removal gently stroke from the body towards the paper on each side with a soft camel's hair brush any disturbed scales. With practice there should not be the least damage done by the thread, which leaves no mark whatever if _moved at once_ when the papers are firmly fixed. If they should be left on carelessly, or by any mistake, the threads will be certain to mark every butterfly, to their complete disfigurement.

Keep the blocks which contain the set-out butterflies in a dry cupboard or other safe place. When thus drying they fall an easy prey to earwigs, wasps, ants, cockroaches, and such like "small beasts," which will strip off all the bodies on a block in a single night. They should not be exposed to too bright a light whilst drying on the blocks, or they often suffer in colour. When single specimens have to be set out it is easy to work the thread by putting a pin through the knot and holding down the other end with the left-hand forefinger until the paper is fixed, and then treating the other wings in like manner.

It is advisable to leave the butterflies on the blocks for about a week, though the surest test is to touch the body gently with a pin, and if _quite hard_, it is safe to remove the insects to a store box without fear of the wings springing. After removing the butterflies, pass over the surface of the block some hard substance, such as the back of an ivory-handled knife, to rub down any little roughness made by the pins on the surface, where the wings are placed, when setting any fresh insects on the same block.

Most of the butterflies are easily reared through all their stages, from the eggs up to the perfect insect. This is by far the most interesting part of the study. Until within the last few years, when the writer of these chapters pressed some of his friends to look more closely into the life histories of our common butterflies, it was the custom of some naturalists to sneer at "butterfly-catchers." Since then a wonderful book has been published on the butterflies of the Eastern portion of North America by Mr. Scudder, and all these scoffers must feel very small when they see such splendid science in the study of butterflies. Now, many people, who never thought of rearing a butterfly, are giving careful attention to them in all their stages.

Several kinds of butterflies are readily induced to lay their eggs in captivity when carefully managed. Various species differ much in this--some may be depended upon with certainty, such as the "green-veined white" (_Pieris napi_), which will deposit its eggs at night upon a piece of watercress, under the influence of a warm room, and the bright light of a paraffin lamp. This species, however, is quite an exception, for, as a rule, every attention should be given to copying their natural surroundings as closely as possible. A good plan is to have ready planted in a large flower-pot a plant of the food of the particular species from which it is desired to have eggs, or, as they are called by the entomologists, the ova--that being, as you know, the plural of ovum, the Latin for an egg. Having got your plant nicely established in its flower-pot, buy a piece of wire-netting, about a foot wide, and bend it round so as to fit just _inside_ the flower-pot. By cutting the wire so as to overlap a little, it is easy to twist or hook the ends, so as to make a cylinder to just fit inside the pot. Then cover this with very open muslin all round and over the top, neatly stretched, so as not to look untidy or to stop a single ray of sunshine which can get through. Having had several of these cages prepared, they may be used at the moment when you bring home the freshly-caught females.

The sooner the female butterflies are placed in the cage the better, for if they remain too long in the pill-box they are apt to get too dry, and so never recover enough to deposit their ova. After firmly tying the cage to the pot, do not disturb them when once in the cages, so long as they are alive; but leave them out of doors, where they get all the sunlight or rain. If the plant be watered, that is best done by soaking the flower-pot in water up to two-thirds the height of the soil, and not by removing the cage. Still, in dry weather it is best to sprinkle the cage with water, so that the captive may drink, which they often require to do.

Another way, especially in the case of small butterflies, is to use large glass jam-pots, with a piece of muslin tied over the top. In these pots should be a little sprig of food-plant in a small bottle of water, and also a bit of damp sponge to keep up a moist atmosphere, without which there will rarely be any eggs. The pots may be placed in the sunlight in a room near an open window, but care should be taken that the glass does not get too hot, or both parent and eggs may be killed. When the eggs hatch, never, if possible, touch, except with a camel-hair brush, the young caterpillars--or larvæ as they are scientifically called, that being the plural for larva, a single caterpillar. Pupa is the singular, and pupæ the plural, for the chrysalis; imago the singular, and imagines the plural, for the perfect insects or complete butterflies. These scientific terms are quite easy to learn, and are the best to use when referring to the various stages of insects generally.

In selecting females for depositing ova, take those which are a little worn, and not too recently emerged from pupæ, as they are the more likely to produce fertile eggs.

When the ova hatch, watch them very closely, at least three or four times a day. If they are on growing food, do not touch them at all, but if they require moving for any reason, a soft, sharp-pointed camel-hair pencil is the best tool to use.

Glass jam-pots are very nice for feeding young larvæ of any kind. The method is, to change the food daily, taking care to remove at the same time all dirt made by the larvæ, which is called "frass." Cleanliness in rearing larvæ is the first consideration, and the next most important thing is to always gather their food from the same tree as that from which they began to feed when hatched. If they are fed on growing plants this does not, of course, apply. Tie over the mouth of the pot with fine unglazed calico, and over this place a piece of glass so as to stop, as far as possible, the drying of the food plant in the jar. Be very particular to supply the fresh food always quite dry, and never in a wet condition, which is apt to give the larvæ diarrh[oe]a, to which in captivity they are very subject. Never give more food than the young larvæ are likely to eat, increasing the supply as they get older.

When changing the larvæ always count them, or some will be lost and thrown out with the withered food. The best plan is to spread out a sheet of white paper on a table, and empty the contents of the jar on it. Then examine the interior of the jar, seeing that every little one is out. Having cleaned it out with a clean, dry duster, put in the fresh food.

Then lift in with the hair-pencil any active larvæ. Those which are sulky-looking on the leaves clip off with part of the leaf, and drop into the jar. They may be changing their skin, and, if disturbed then, will probably not recover. The food should be changed at least once every day.

While growing, larvæ of butterflies generally like plenty of light, but it is unsafe to leave the sunshine too long on the jars, in case the living contents get baked, as will the food certainly. Some species while in the larval stage, feed only at night, hiding away in the daylight. These are matters which will soon be found out by experience.

We have never heard of any one having reared all the British species through their stages, but we know one friend who reared no less than eighteen different kinds through, from ova to imagines, in a single season.

$Moth Catching.$--Students of natural history in search of moths which they may identify by a reference to such works upon the subject as those by the Rev. J. G. Wood, will find an interesting method of catching them in preparing "Treacles." The fancy "golden syrups" of the kitchen should be avoided. Ask the grocer to get common treacle--green treacle they call it in the trade. To a pound of this will be added a wineglassful of stale beer and about three-quarters of a wineglassful of the most inferior rum you can buy. A few drops of oil of aniseed will improve this dreadful concoction. Do not add the rum, beer, and aniseed to the treacle at once, but keep them in a bottle apart until you are going to use the mixture.

With a companion who carries a net, look out now for isolated trees that have a rough bark. Do not waste attention on dead trees, fences, nor chestnut trees, willows, nor flowering ivy. In warm, damp weather when there is no moon, go out with a bottle of this mixture and a house-painter's brush, "a sash tool," as painters call it, will serve you well, and a lantern, some pill-boxes or similar small receptacles. Having selected a tree daub it well with your mixture in a patch about a foot long and half a foot broad. So pass from tree to tree. Come back at last to the first tree again. Your companion should hold the net under the treacle patch for some of the moths that have come to enjoy the rum and treacle will fall when you turn the lantern light upon them. Those that do not may be taken from the tree by an upward scoop of a pill-box, and then secured by the lid. Try to avoid getting the sticky mixture upon the handle of the brush and upon your hands, for it will prevent your deft manipulation of your pill boxes. After the first night very little treacle will be needed to freshen the patches, but the mixture may be used freely on your first round. The treacling season begins about March 21 and goes on until the end of April. May does not yield many moths, nor the first week in June, but after that you may go round again with your bottle until the end of September. You may find sometimes that toads and bats poach on your preserves.

Another way to secure specimens of moths is to make a moth trap. Our diagram gives a plan of it, that is a representation of it as seen from above if we look down at it with the lid off. A, B, C, D is a box. It may be made for the purpose, or a soap box or other case may be purchased from the grocer for a few coppers. E, F, and G are panes of glass, held in grooves. H is another pane of glass which comes up to the lid, and cuts the box into two unequal parts. J is the reflector of a lighted lamp placed in front of it. There will need to be a hole in the lid over the lamp, and a flower pot upside down may be put over this hole. It is best to have three doors into the larger compartment; one in the lid and one in each of the two sides, K and L, so that two hands may be used in putting the moths that come to the light into pill boxes.