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"What hand would crush the silken-wingèd fly, The youngest of inconstant April's minions, Because it cannot climb the purest sky, Where the swan sings, amid the sun's dominions? Not thine."

Shelley.

"Do not mash your specimens!"—The Professor.

COLLECTING APPARATUS

Nets.—In the capture of insects of all orders, and especially of butterflies and moths, one of the most important instruments is the net. German naturalists make use of what are known as shears (Scheren), which are made like gigantic scissors, having at the end two large oval rings upon which wire gauze or fine netting is stretched. With this implement, which looks like an old-fashioned candle-snuffer of colossal size, they succeed in collecting specimens without doing much injury. Shears are, however, not much in vogue among the naturalists of other countries. The favorite instrument for the ordinary collector is the net. Nets may be made in various ways and of various materials. There are a multitude of devices which have been invented for enabling the net to be folded up so as to occupy but little space when not in use. The simplest form of the net, which can be made almost anywhere, is constructed as follows: A rod—preferably of bamboo, or some other light, stiff material—is used as the handle, not more than five feet in length. Attached to this at its upper end, a loop or ring made of metal, or some moderately stiff

Fig. 43.—Plan for folding net-ring: c, halves of ring detached; b, upper joint of the halves; a, ring set; d, cap of ferrule; f, cap of ferrule, showing screw in place; e, screw (Riley).

Fig. 44.—a, net; b, ferrule to receive handle; c, wire hoop to be fastened in the upper end of the ferrule (Riley).

Fig. 45.—a, ring of metal tied with wire at a; b, ferrule; c, plug put in before pouring in solder (Riley).

yet flexible material, should be tied securely. Upon this there should be sewed a bag of fine netting, preferably tarletan. The bag should be quite long, not less than eighteen inches deep; the ring should be not less than a foot in diameter. Such a net can be made at a cost of but a few cents, and will be, in most cases, as efficient as any of the more expensive nets which are more carefully constructed. A good, cheap ring for a net may be made by using the brass ferrule of a fishing-rod. The ferrule should be at least three quarters of an inch in diameter. Into this insert the ends of a metal ring made by bending brass, aluminium, or iron wire into the proper form. When the ends have been inserted into the ferrule, melted solder or lead may be poured into it, and the ends of the wire forming the ring will be thus firmly secured in the ferrule. The ferrule can then be inserted into its mate placed at the end of a bamboo rod. I have commonly obtained for this purpose the last joint or butt of a fishing-rod as the handle of a net. Such a handle can often be purchased for a small sum from a dealer in fishing-rods. It can be made very cheaply. Any kind of a stick, if not too heavy, will do. It is sometimes convenient to have it in your power to lengthen the handle of your net so as to reach objects that are at some elevation above the head, and for this purpose I have had nets made with handles capable of being lengthened by jointed extensions. In collecting in tropical countries, among tall shrubbery and undergrowth, nets thus made, capable of having their handles greatly lengthened, have often proved serviceable. One of the most successful collectors I have ever had in my employment made his net by simply bending a piece of bamboo into the form of the frame of an Indian snow-shoe, to which he attached a handle about a foot and a half in length, and to this he affixed a bag of netting. He was, however, a Japanese, and possessed a singular dexterity in the capture of specimens with this simple apparatus to which I myself never attained. When tarletan cannot be had, ordinary mosquito-netting will do as the material for the bag. It is, however, too coarse in the mesh for many delicate and minute species. Very fine netting for the manufacture of the bags is made in Switzerland, and can be obtained from reputable dealers.

In order to protect and preserve the net, it is well to bind it with some thin muslin at the point where it is joined to the ring. Nets are sometimes made with a strip of muslin, about two inches wide, attached to the entire circumference of the ring, and to this strip of muslin the bag is sewed. For my part, I prefer gray or green as the color for a net. White should be avoided, as experience shows that a white net will often alarm an insect when a net of darker material will not cause it to fly before the collector is ready to bring the net down over the spot where it is settled.

Collecting-Jars.—In killing insects various methods have been used. In practice the most approved method is to employ a jar charged with cyanide of potash or with carbonate of ammonia. For large moths and butterflies cyanide of potash and carbonate of ammonia serve very well, but it must be remembered that carbonate of ammonia bleaches insects which are green in color. It is well, in my judgment, to use a drop or two of chloroform in the jar charged with carbonate of ammonia, for the collection of diurnal lepidoptera. By putting a few drops of chloroform into the jar, the insect is anesthetized, and its struggles are made quickly to cease. The principal objection to chloroform is the fact that it induces rigidity of the thoracic muscles, which subsequently sometimes interferes with handsome setting.

Fig. 46.—Cyanide-jar prepared for use: P, perforated cardboard; Cy, lumps of cyanide of potash.

Fig. 47.—Piece of paper punctured and slit for pasting over the cyanide in the collecting-jar.

In the preparation of the poisoning-jar it is well to use a jar which has a ground-glass stopper, and the mouth of which is about three inches in diameter. This will be large enough for most specimens. The one-pound hydrate of chloral jars, provided with glass stoppers and sold by Schering, make the neatest collecting-jars that are known to the writer. I have found it well to have such jars partly covered with leather after the fashion of a drinking-flask. An opening in the leather is left on either side, permitting an inspection of the contents of the jar. The leather protects from breakage. At the bottom of such a jar a few lumps of cyanide of potash, about the size of a filbert, should be placed. Over this may be laid a little cotton, to prevent the lumps from rattling about loosely at the bottom of the jar. Over the cotton there is pasted a sheet of strong white paper, perforated with a multitude of holes. In securing the white paper over the cyanide, the writer has resorted to a simple method which is explained in the annexed diagram. A piece of paper is placed under the jar, and a circle the size of the inside of the jar is traced upon it. Then a disk is cut out about three quarters of an inch greater in diameter than the original circle (Fig. 47). The paper is punctured over the entire surface included within the inner line, and then, with a scissors, little gashes are made from the outer circumference inward, so as to permit of the folding up of the edge of the disk. A little gum tragacanth is then applied to these upturned edges; and it is inserted into the jar and pasted securely over the cyanide by the upturned flaps. A jar thus charged will last for a long time, if kept properly closed when not in use. Cyanide of potash has a tendency to deliquesce, or melt down in the presence of moisture, and in very humid climates or damp places, if the jar is not kept well stoppered, the cyanide will quickly become semi-fluid, the paper will become moist, and specimens placed in the jar will be injured or completely ruined. It is well, however, to bear in mind the fact that the fumes of hydrocyanic acid (prussic acid), which are active in producing the death of the insect, will not be given off in sufficient volume unless there is some small amount of moisture present in the jar; and in a very dry climate the writer has found it sometimes necessary to add a drop or two of water from time to time to the cyanide. The same method which has been described for charging a jar with cyanide of potash can be employed in charging it with carbonate of ammonia.

Fig. 48.—Method of disabling a butterfly by pinching it when in the net.

Field-Boxes.—In collecting butterflies it is often possible to kill, or half kill, the specimens contained in the net by a smart pinch administered to the insect by the thumb and the first finger, the pressure being applied from without the net (Fig. 48). This mode of procedure, however, unless the operator is careful, is apt to somewhat damage the specimens. The writer prefers to hold the insect firmly between the thumb and the first finger, and apply a drop or two of chloroform from a vial which should be carried in the upper left-hand vest-pocket. The application of the chloroform will cause the insect to cease its struggles immediately, and it may then be placed in the poisoning-jar, or it may be pinned into the field-box. The field-box, which should be worn at the side, securely held in its place by a strap going over the shoulder and by another strap around the waist, may be provided with the poisoning apparatus or may be without it. In the former case the box should be of tin, and should have securely fastened in one corner some lumps of cyanide, tied in gauze. The box should be very tight, so that when it is closed the fumes of the cyanide may be retained. The bottom should be covered with cork, upon which the specimens, as they are withdrawn from the poisoning-jar, should be pinned. It is well to bear strictly in mind that it is a mistake to continue to put one specimen after another into the poisoning-jar until it is half filled or quite filled with specimens. In walking about the field, if there are several insects in the jar at a time, they are likely to become rubbed and their beauty partially destroyed by being tossed about as the collector moves from place to place; and a large insect placed in a jar in which there are one or two smaller insects will in its death-struggles possibly injure the latter. So, as fast as the insects are partially asphyxiated, or deprived of the power of motion, they should be removed from the poisoning-jar to the poisoning-box, where they are pinned in place and prevented from rubbing one against the other. Some collectors prefer simply to stun the insects, and then pin them into the field-box, where they are left, in whole or in part, to recover their vitality, to be subsequently put to death upon the return of the collector from the field. This mode of procedure, while undoubtedly it yields in the hands of a skilful operator the most beautiful specimens, appears to the writer to be somewhat cruel, and he does not therefore approve of it.

Plate IV.

The Use of the Net.—In the use of the net the old saying is true that "practice makes perfect." The bag of the net should be sufficiently long to allow of its being completely closed when hanging from the ring on either side. It is possible to sweep into the net an insect which is fluttering through the air, and then by a turn of the hand to close the bag and to capture the specimen. When the insect has alighted upon the ground it is best to clap the net over it and then to raise the net with one hand. Very many species have the habit of flying upward. This is particularly true of the skippers, a group of very vigorous and swift-flying butterflies. The writer prefers, if possible, to clap the net over the specimens and then to allow them to rise, and, by inserting the wide-mouthed collecting-jar below, to capture them without touching them at all with the fingers. So far as possible the fingers should not be allowed to come in contact with specimens, whether in or out of the net, though some persons acquire an extremely delicate yet firm touch which enables them to handle the wings of frail species without removing any of the scales. Nothing is more unsightly in a collection than specimens that have been caught and rubbed by the fingers.

Baits.—Moths are frequently taken by the method of collecting known as "sugaring." But it may also be employed for butterflies. For this purpose a mixture of beer and cheap brown sugar may be used. If the beer be stale drippings, so much the better. In fact, it is well, if the collector intends to remain in one locality for some time, to make a mixture of beer and sugar some hours or a day in advance of its application. In semi-tropical countries a mixture of beer and sugar is hardly as good as a mixture of molasses and water into which a few tablespoonfuls of Jamaica rum have been put. A mixture thus prepared seems to attract more effectually than the first prescription. Having provided a pail with a quart or two of the mixture, the collector resorts to the point where he proposes to carry on his work. With an ordinary whitewash brush the mixture is applied to the trunks of trees, stumps, fence-rails, and other objects. It is well to apply the mixture to a series of trees and posts located on the side of a bit of woodland, or along a path through forests, if comparatively open and not too dense. The writer has rarely had success in sugaring in the depths of forests. His greatest success has always been on paths and at the edge of woods. Many beetles and other insects come to the tempting sweets, and separate jars for capturing these should be carried in the pocket. The collector never should attempt to kill beetles in the same jar into which he is putting butterflies. The hard, horny bodies and spiny legs of beetles will make sad havoc with the delicate wings of butterflies.

Many other baits besides this may be employed to attract insects. Some writers recommend a bait prepared by boiling dried apples and mashing them into a pulp, adding a little rum to the mixture, and applying this to the bark of trees. In tropical countries bananas, especially rotten bananas, seem to have a charm for insects. The cane-trash at sugar-mills is very attractive. If possible, it is well to obtain a quantity of this trash and scatter it along forest paths. Some insects have very peculiar appetites and are attracted by things loathsome. The ordure of carnivorous animals seems to have a special charm for some of the most magnificently colored and the rarest of tropical butterflies. A friend of mine in Africa, who collected for me for a number of years, used to keep civet-cats, the ordure of which was collected and placed at appropriate points in the forest paths; and he was richly rewarded by obtaining many insects which were not obtained in any other way. Putrid fish have a charm for other species, and dead snakes, when rankly high, will attract still others. It may be observed that after the trees have been treated for a succession of days or nights with the sweetening mixture spoken of above, they become very productive. When collecting in Japan I made it a rule to return in the morning to the spots that I had sugared for moths the evening before, and I was always amply repaid by finding multitudes of butterflies and even a good many day-flying moths seated upon the mossy bark, feasting upon the remnants of the banquet I had provided the evening before. There is no sport—I do not except that of the angler—which is more fascinating than the sport derived by an enthusiastic entomologist from the practice of "sugaring." It is well, however, to know always where your path leads, and not to lay it out in the dusk, as the writer once did when staying at a well-known summer resort in Virginia. The path which he had chosen as the scene of operations was unfortunately laid, all unknown to himself, just in the rear of the poultry-house of a man who sold chickens to the hotel; and when he saw the dark lantern mysteriously moving about, he concluded that some one with designs upon his hens was hidden in the woods, and opened fire with a seven-shooter, thus coming very near to terminating abruptly the career of an ardent entomologist.

Beating.—There are many species which are apparently not attracted by baits such as we have spoken of in the preceding paragraph. The collector, passing through the grove, searches diligently with his eye and captures what he can see, but does not fail also with the end of his net-handle to tap the trunks of trees and to shake the bushes, and as the insects fly out, to note the point where they settle, and then make them his prey. It is well in this work, as in all collecting, to proceed somewhat leisurely, and to keep perfectly cool. The caricature sometimes found in newspapers of the ardent lepidopterist running like a "quarter-back" across a ten-acre lot in quest of some flying insect does not represent the truly skilful collector, whose movements are more or less stealthy and cautious.

THE BREEDING OF SPECIMENS

By breeding it is possible to obtain specimens in the most perfect condition. Bred specimens which have not had an opportunity to fly are always preferred on account of their freshness of color and perfection of form. A great many species which apparently are exceedingly rare may often be obtained in considerable numbers by the process of breeding, the caterpillar being more readily found than the perfect insect. Although the process of breeding involves a good deal of labor and care, it affords a most delightful field for observation, and the returns are frequently of the very greatest value.

How to Get the Eggs of Butterflies.—The process of breeding may begin with the egg. The skilful eye of the student will detect the eggs of butterflies upon the leaves upon which they have been deposited. The twig may be cut and placed in a vase, in water, and kept fresh until the minute caterpillar emerges, and then from time to time it may be transferred to fresh leaves of the same species of plant, and it will continue to make its moults until at last it is transformed into a chrysalis, and in due season the butterfly emerges. Eggs may frequently be obtained in considerable numbers by confining the female under gauze, with the appropriate food-plant. A knowledge of the food-plant may often be obtained by watching the female and observing upon what plants she deposits her eggs. The exceedingly beautiful researches of Mr. W.H. Edwards were largely promoted by his skill in inducing females to oviposit upon their food-plants. He did this generally by confining the female with the food-plant in a barrel or nail-keg, the bottom of which had been knocked out, and over the top of which he tied mosquito-netting. The plant was placed under the keg. The insects thus confined may be fed with a mixture of honey and water placed upon the leaves.

In collecting caterpillars it is well to have on hand a number of small boxes in which to place them, and also a botany-box in which to bring from the field a supply of their appropriate food.

The process of breeding may begin with the caterpillar. The collector, having discovered the caterpillar feeding upon the branch of a certain plant, provides the creature with a constant supply of the fresh foliage of the same plant, until it finally pupates.

Fig. 49.—Cheap form of breeding-cage: G, lid covered with mosquito-netting; E, pan of earth; B, bottle for food-plant.

Breeding-Cages.—Various devices for breeding caterpillars and rearing moths and butterflies are known. One of the most important of these devices is the breeding-cage, which is sometimes called a vivarium. The simplest form of the vivarium is often the best. In breeding some species the best method is simply to pot a plant of the species upon which the larva is known to feed, and to place the potted plant in a box over which some mosquito-netting is tied. The writer frequently employs for this purpose cylinders of glass over the top of which perforated cardboard is placed. This method, however, can be resorted to only with the more minute forms and with plants that do not attain great height. Another form of vivarium is represented in the adjoining woodcut (Fig. 50). The writer has successfully employed, for breeding insects upon a large scale, ordinary store boxes provided with a lid made by fastening together four pieces of wood, making a frame large enough to cover the top of the box, and covering it with gauze. The food-plant is kept fresh in bottles or jars which are set into the boxes. Be careful, however, after you have put the branches upon which the caterpillars are feeding into the jars, to stuff something into the neck of the jar so as to prevent the caterpillar from accidentally getting into the water and drowning himself—a mishap which otherwise might occur. When breeding is undertaken on a still larger scale, it may be well to set apart for this purpose a room, preferably in an outbuilding, all the openings leading from which should be carefully closed so as to prevent the escape of the caterpillars.

Fig. 50.—Breeding-cage: a, base, battened at g to prevent warping; b, removable body of cage, inclosing zinc pan, f, f, containing jar for plant, d, and filled with five inches of soil, e; c, removable top, covered with wire gauze. The doors and sides are of glass (Riley).

How to Find Caterpillars.—Many species of caterpillars are not hard to discover; they are more or less conspicuous objects, and strike the eye. Some species conceal themselves by weaving together the leaves of the plant on which they feed, or by bending a single leaf into a curved receptacle in which they lie hidden. Others conceal themselves during the daytime about the roots of trees or under bark or stones, only emerging in the night-time to feed upon the foliage. The collector will carefully search for these. The presence of caterpillars is generally indicated by the ravages which they have committed upon the foliage. By carefully scanning a branch the collector will observe that the leaves have been more or less devoured. Generally underneath the tree will be found the frass, or ejectamenta, of the caterpillar. The presence of the ejectamenta and the evidence of the ravages committed by the larvæ upon the foliage will give the collector a clue to the whereabouts of the caterpillar. The writer has found it generally advantageous to search for caterpillars that feed upon trees along the wide, sandy margins of brooks and rivers. The frass is easily discovered upon the sand, and by casting the eye upward into the foliage it is often easy to detect the insect. The pavements in towns and cities which are bordered by trees may also very well be scanned for evidence of the presence of caterpillars. A favorite collecting-ground of the writer is one of the large cemeteries of the city in which he lives, in which there are numerous trees and a great quantity of shrubbery. Wood-boring species, as a rule, are more difficult to obtain and rear than those that feed upon the foliage.

Hibernating Caterpillars.—While some difficulty attends the preservation of chrysalids in the case of those species which pupate in the fall and pass the winter in the chrysalis state under the ground, far more difficulty attends the preservation of species which hibernate in the caterpillar state. As a rule, it is found best to expose the boxes containing these species in an ice-house or other cold place, keeping them there until there is available an abundant supply of the tender shoots of the plant upon which they are in the habit of feeding. They may then be brought forth from cold storage and placed in proximity to the food-plant, upon which they will proceed to feed.

THE PRESERVATION OF SPECIMENS

Papering Specimens.—When time and opportunities do not suffice for the proper preparation of butterflies for display in the permanent collection, the collector may, in the case of the larger species, conveniently place them in envelopes, with their wings folded (Fig. 51), and they may then be stored in a box until such time as he is able to relax the specimens and properly mount them. Thousands of insects are thus annually collected. The small drug envelopes, or the larger pay-roll envelopes, which may be bought in boxes by the thousand of any stationer for a comparatively small sum, are preferable because of their convenience. Many collectors, however, paper their specimens in envelopes which they make of oblong bits of paper adapted to the size of the insect. The process of making the envelope and of papering the insect is accurately depicted in the accompanying cut (Fig. 52). The writer finds it good in the case of small butterflies to place them in boxes between layers of cheap plush or velvet. A small box, a few inches long, may be provided, and at its bottom a layer of velvet is placed; upon this a number of small butterflies are laid. Over them is placed a layer of velvet, with its soft pile facing the same side of the velvet at the bottom. On top of this another piece of velvet is laid, with its pile upward, and other specimens are again deposited, and over this another piece of velvet is laid, and so on. If the box is not filled full at once, it is well to have enough pieces of velvet cut to fill it, or else place cotton on top, so as to keep the layers of velvet from moving or shaking about. A yard or two of plush or velvet will suffice for the packing of a thousand specimens of small butterflies.