Chapter XIV: Seaweeds, by W. H. Grattann 195 (2)
There can be no doubt but that egg-hunting is a very profitable occupation, and far more remunerative than most people dream of, particularly as a means of acquiring the Sphinges, Bombyces, and Pseudo-bombyces. Eggs, speaking generally, are to be found on the plants to which the various species are attached; and a knowledge of the time during which the species remains in the egg state, as well as the appearance of the eggs as deposited in nature, should if possible be acquired previous to proceeding to hunt. The most practical way of ascertaining the food and time is to watch the parent insect in the act of depositing her ova; but when the plant has been thus discovered, the best way is to capture her, and induce her to lay at our home. When eggs are inconspicuous, of small dimensions, or artfully concealed, the use of a magnifying glass is invaluable.
Eggs may be preserved by plunging them in boiling water or piercing them with a very fine needle, or they may have their contents squeezed out and be refilled by means of a fine blowpipe, with some coagulable tinted fluid; but the shells themselves, after the escape of the larvæ, form, when mounted, beautiful objects for the microscope.
The three most successful plans of obtaining caterpillars are searching, beating, and sweeping. The first requires good eyesight and a certain amount of preparatory knowledge; the others are a sort of happy-go-lucky way of collecting, useful enough and profitable in their way, but affording a very limited scope for the exercise of the wits. In searching for larvæ, the chief thing is to observe the indications of their presence. A mutilated leaf, a roughened bark, a tumid twig, a sickly plant, an unexpanded bud, an abortive flower, or a windfall fruit, should at once set us thinking as to the cause; or, again, the webs, the silken threads, the burrowings and trails, or the cast-off skins of larvæ, may first call our attention to their proximity. Of course, larvæ may be found on almost all plants, as well as in the bark, stems, or wood of many; but the collector should fortify himself with a knowledge of what each plant is likely to produce, and hunt accordingly; for though indiscriminate collecting may sometimes be successful, it does not tend to improve the intellectual powers.
Beating is the more applicable method of working trees and bushes. It is carried out by jarring the larvæ from their positions by the aid of a stick or pole, in such a manner that they will fall into an inverted umbrella, or net; or a sheet may be spread beneath for their reception. Sweeping with a strong net, passed from side to side with a mower-like movement, is better adapted for working low ground-herbage. The umbrella net, shown in Fig. 11, is, perhaps, the best for the purpose. It is constructed by hinging two lengths of jack-spring on two pieces of brass, and adapting them to the stick of the net, the upper piece of brass being fixed, the lower movable.
When captured, larvæ should be transferred to chip boxes, or else to finely and freely perforated tins, the latter better preserving the food. A very handy box for the purpose is formed by fitting a second lid on to the bottom of a chip box, and then cutting from the second lid and bottom a hole, as shown in Fig. 12 (2); larvæ may then be inserted through the hole; but when the lid is shifted round, and the holes are not opposite, of course there will be no opening, as in Fig. 12 (1), and the contents are secured from escape.
Larva preserving is carried out by first killing, and then squeezing and extracting the contents through the anal orifice by means of a crochet hook.
When this has been done, the skin is inflated, but not to such an extent as to distend the segments, and is kept thus inflated while it is being dried in a heated metal chamber. Afterwards, if the colours are observed to have faded, they may be cautiously restored by the application of paint. These objects, mounted on suitable artificial leaves, are then ready for the cabinet.
Chrysalis collecting is conducted according to the situation of the object sought. Some are to be found in the chinks of bark or under loose bark, which may be detached by means of a powerful lever. Some are suspended from trees, bushes, copings, hanging head downwards, or girded by silken threads to low plants or walls; others are to be found in the stems or trunks of their food-plants; many are concealed in cocoons of more or less perfect construction, others again amongst fallen leaves, but the majority are to be met with under the surface of the ground; in which case we shall have to dig for them by the aid of a trowel or broad chisel. The best situations for subterranean pupæ are open park-like fields, borders of streams, open spaces in fir woods, and they are usually situated within a foot or so of the tree trunks, at the depth of two or three inches, though sometimes considerably deeper. Of course both larvæ and pupæ of aquatic species will have to be sought for in their element, among the plants they frequent.
Chrysalis preserving is a simple matter: the pupæ may be killed by plunging them into hot water or by baking; frequently, however, we find that the natural polish disappears with death, and this may be restored by varnishing. It is advisable that the cocoons also, where practicable, should be preserved, to give a notion of their appearance in nature.
Moths and butterflies may be sought for at rest or on the wing. They may be disturbed from their hiding places or they may be attracted by various alluring baits.
At rest on stems of grasses and other plants butterflies may be taken on dull, sunless days; but it requires some experience to detect a butterfly with its wings raised up over its back: the little "Blues" may thus be freely boxed in their localities. Again, such butterflies as hybernate may be found in old sheds and outhouses, or under stacks.
Moths may be taken at rest on tree trunks, palings, and walls, or amongst foliage and ground herbage. Some species are to be freely captured in this way after their evening flight is over. Of course, for evening work, a lantern to assist our vision will be indispensable.
On the wing, some butterflies are exceedingly active, others comparatively sluggish; some fly high, others low. In hunting them, the chief points to be remembered are not to alarm, but rather cautiously to stalk our game, and strike, when we have an opportunity, with precision. It is important also to avoid throwing a shadow over them, and it is a good plan to get to windward of them--anything like flurry will be fatal to success.
Moths which fly by day may be chased in the same manner, but some may be observed disporting themselves round trees; these must be watched, and netted as they now and then descend. Others fly at a very low altitude, and are only brought into the field of vision by our assumption of the recumbent position. At night again, though we watch for anything stirring the air, among the trees or the herbage, our tactics are somewhat modified; for, if the insect be of whitish colour, we should so place ourselves that its form will stand boldly out against a mass of dark foliage, whereas, if it be dingy in hue, we must take the sky for our background.
Disturbing insects, and thus causing them to start forth, and so render themselves visible, is another method of collecting. This is carried out in various ways.
First, the occupants of high trees may be expelled by jarring the trunk with a heavily loaded mallet, or by thwacking the trunk with a long hazel stick; but a sharp look-out must be kept, for some sham death, and fall plump down, while others make off as fast as they can. Other plans are to pelt the trees with stones, or pump on them with a powerful garden engine, or beat them with a long pole; and of all tress the most profitable for this purpose is the yew; though firs, oaks, beeches, and other trees are not to be despised.
For beating bushes there is nothing better than a walking-stick, and for low herbage a long switch passed quickly from side to side with a tapping movement is best adapted. The tenants of tree trunks may be disturbed by brushing the surface with a leafy little bough, or, better still, by the use of a strong fan, with which a powerful blast may be driven, the net being held in such a position as to intercept such insects as are blown off.
Thatch-beating in the autumn is a very profitable employment, particularly in the matter of _Depressariæ_. Sweeping need only be mentioned here, for moths collected by the process are anything but perfect insects.
There are various methods of attracting moths and butterflies. The first is effected by confining a virgin female in a muslin cage, the frame of which may be very readily formed by bending three pieces of cane into circles, and fixing these together at right angles, as shown in Fig. 13. When this baited cage is placed in a favourable position, and the weather is propitious for the flight of the males, the latter will, in some cases, congregate, and may be freely captured.
Then, the food-plant of the species is an attraction at which we stand the best chance of procuring impregnated females.
Various kinds of blooms possess alluring qualities for insects: of these, sallow and ivy are the greatest favourites with collectors. They should be worked after dusk by means of a lantern and net; but the combination of a lantern fixed to a long stick, with a shallow net beneath and a little in advance of it, as shown in the cut, is the apparatus best adapted for the purpose; the object of the net being to intercept any insects which may happen to fall under the stimulus of light. These attractions should be first well searched over, and afterwards, a sheet (split if necessary) having been carefully spread below the bushes, a gentle shaking should be administered. Besides these blossoms, heather, ragwort, bugloss, catchfly, bramble, various grasses, and a vast number of other flowers, are wonderfully attractive. In working patches of bloom we should remain stationary and strike as the visitors arrive. Again, over-ripe fruit, the juicy buds of certain trees, sap exuding from wounds in trees, are all more or less attractive. The secretion of aphides, commonly called honeydew, observable in hot seasons on the leaves of nettles and various other plants and trees, is also well worth attention, and is at times very productive of insects.
Sugaring is the next attraction, and a very important one it is. "Sugar" may be prepared by boiling up equal quantities of coarse "foots" sugar and treacle in a sufficient quantity of stale beer, a small quantity of rum being added previous to use, and also, if considered advisable, a flavouring of jargonelle pears, anise-seed, or ginger-grass. This mixture should be applied by means of a small paint brush to the trunks of trees, to foliage, flowers, tufts of grass, or indeed to any object which may present a suitable surface; for in some localities we are put to shift to know where to spread our sweets. This operation should be performed just before dusk, and soon afterwards the baited spots should be visited and, by the aid of a lantern gently turned on them, examined, a net being held beneath the while. The best form of net for the purpose is formed by socketing two paragon wires into a Y-piece and connecting their diverging extremities by a piece of catgut, as shown in Fig. 15. The catgut, being flexible, will adapt itself (see the dotted line) to the surface of a tree trunk when pressed against it. With regard to insects captured at sugar, they are usually remarkably quiet, and may be boxed without difficulty, and, with a few exceptions, may be conveyed home in the boxes, care being taken to let each have a separate apartment. The boxes should be strengthened with strips of linen pasted round the joints, as shown in Fig. 16, otherwise accidents may occur, particularly on wet evenings or on rough ground. The skittish individuals may be best captured by means of the sugaring drum, of which a cut is given in Fig. 17. This apparatus consists of a cylinder, one end of which is covered with gauze, the other provided with a circular valve, which works in a slit. For use, the valve is opened and the cylinder placed over the insect, which naturally flies towards the gauze; then the valve is closed, the corked piston, shown at the upper part of the cut, placed against it, the valve re-opened, the piston pushed up to the gauze, the insect pinned through the gauze, and the piston withdrawn with the insect transfixed to it.
Light is another most profitable means of attracting. The simplest way is to place a powerful moderator lamp upon a table in front of an open window which faces a good locality, and then wait net in hand for our visitors, which usually make their appearance late in the evening, and continue to arrive until the small hours. Those who prefer it can use the American moth-trap, which is self-acting, detaining such insects as may enter its portals, or those who can afford the space may fit up a room on the same principle. Street lamps are very profitable certain localities, and amply reward the collector who perseveringly and minutely examines them. The apparatus depicted in Fig. 18 is very useful for taking off such insects as may be on the glass of the lamp: it consists of a cyanide bottle attached by a ferrule to the end of a sufficiently long stick. When placed over an insect, stupefaction is quickly produced. A net of the shape represented in Fig. 19 is also very useful for getting at the various parts of the lamp.
The best methods of stupefying and killing insects on the field is the cyanide bottle, prepared by placing alternate layers of cyanide of potassium and blotting-paper in the bottom of a wide-mouthed bottle, the mouth of which is accurately stopped with a cover, which is better for the purpose than a bung. The chloroform bottle, which is generally made with a little nipple, through which the fluid flows slowly out, and covered with a screw-tap, as in the cut 20, is also handy. The chloroform should be dropped over perforations in the box containing our patient, these perforations having been previously made by a few stabs of a penknife. After the fluid is dropped, our thumb should cover it, when the vapour will quickly enter, and the inmate speedily become insensible. Afterwards the _coup de grâce_ may be given to the insect by pricking it under the thorax with the nib of a steel pen dipped in a saturated solution of oxalic acid. If we are smokers, a puff of tobacco may be blown into the box with like result. If we are destitute of any apparatus, and brimstone lucifers for the purpose of suffocating our captures under an inverted tumbler cannot be obtained at some roadside inn, we must fall back on the barbarous practice of pinching the thoraces of such as cannot be carried home in boxes. At home we shall find the laurel jar and ammonia bottle the most useful. The former is made by partially filling a large wide-mouthed bottle or jar with cut and bruised dry leaves of young laurel: if any dampness hang about them, we shall have the mortification of seeing our specimens become mildewed. The latter consists in adding a few lumps of carbonate of ammonia, or some drops of strong liquid ammonia, on a sponge, to the bottle in which our captures, with each box lid slightly opened, have been placed. But it must be borne well in mind, firstly, that ammonia is injurious to the colours of most green insects; and secondly, that if the specimens be not well aired after having been thus killed, the pins with which they are transfixed will become brittle and break. Insects should be left in the ammonia for several hours, and are then in the most delightful condition for setting out.
To pin an insect properly is a most important procedure. The moth, if of moderate dimensions may be rested or held between the thumb and fore finger of the left hand, while the corresponding digits of the right hand operate by steadily pushing a pin through the thorax, bringing it out between the hind pair of coxæ until sufficient of the pin is exposed beneath to steady the insect in the cabinet The direction of the pin should be perpendicular when the insect is viewed from the front, as in Fig. 21; but a lateral view should show the pin slightly slanting forwards, as in Fig. 22. Pins made for the purpose in numerous sizes are sold by Mr. Cooke, of New Oxford Street.
Setting out moths and butterflies is an operation which, if skilfully performed, adds much to the beauty of the future specimens. The method of setting most popular is carried out by means of saddles and braces. These so-called saddles are pieces of cork rounded as in the sectional figure, a groove being cut out for the reception of the bodies of the insects: they are generally strengthened by a strip of wood, upon which they are glued. Braces are wedge-shaped pieces of card or thick note-paper, the thick end strengthened, if necessary, with a disc of card fixed by shoemakers' paste, and pierced with a pin through it, as shown in Fig. 24. The mode of application of these appliances is beautifully shown in Fig. 26[D]. But before these straps can be applied, the wings must first be got into position by means of the setting needle and setting bristle, which are thus manipulated (the setting bristle, by the way, being formed by fixing a cat's whisker and a pin into a piece of cork, at the angle shown in Fig. 25):--After the insect is straightly pinned upon the saddle, and the legs, antennæ, and, if necessary, the tongue, got into position, the left fore-wing is to be pushed or tilted into its place by means of the setting needle, which is merely a darning needle with a handle; and simultaneously it is to be held down by the bristle; then a small brace should be applied to the costa of the fore wing. Next the hind wing should in like manner be adjusted, and as many braces as are considered necessary to keep the wings in their place should be added. Lastly, the right side of the insect should be treated in a similar way.
[D] Figs. 26 and 27 have been kindly lent by Messrs. Reeve & Co.
A very useful mode of setting, invaluable when we are destitute of saddles, is known as "four-strap" setting, and is well explained in Fig. 27. In this case the lower straps are first put into such a position, that when the insect is placed over them the middle of each of the costæ will rest upon them; then the wings are got into position, and the second pair of straps are applied over the wings, the latter retaining their position through the elasticity of their costæ: two more straps are generally added to secure the outer borders of the wings, as shown in the drawing; but these, though advantageous, are not absolutely necessary. The saddles, with their contents, should be kept in a drying house, which is a box adapted for their reception, and freely ventilated, until the specimens are thoroughly dry, when the latter may be cautiously removed, and transferred to the collection.
To preserve our collection from decay, considerable care and attention is necessary. In the first place no insect which is in the least degree suspected of being affected by mites, or mould, or grease, should on any account be admitted to our collections. It is best to be on the safe side and submit every insect received from correspondents, whether mity or not, to quarantine, by which is meant their detention for a few weeks in a box the atmosphere of which is impregnated with some vapour destructive to insect life; such as that of benzole. Our own specimens we should kyanize by touching the bodies of each with a camel's-hair brush dipped in a solution of bichloride of mercury of the strength six grains to the ounce of spirits of wine,--no stronger.
As for mould, it is best destroyed by the application of phænic or carbolic acid, mixed with three parts of ether or spirit. As preventives, the specimens should be kyanized as above. Caution in the use of laurel as a killing agent must be exercised, and the collection must be kept in a dry room.
Grease may be removed by soaking the insects in pure rectified naphtha or benzole, even by boiling them in it if necessary. When the bodies only are greasy, they may be broken off, numbered, and treated as above. After the grease is thoroughly softened, the insects should be covered up in powdered pipeclay or French chalk, which may be subsequently removed by means of a small sable brush. As a precaution against grease, it is advisable to remove the contents of the abdomina by slitting up the latter beneath with a finely pointed pair of scissors before they are thoroughly dry, and packing the cavities with cotton wool. The males, especially of such species as have internal feeding larvæ, should be thus treated.
Some prefer to keep their collections in well-made store boxes, which possess many advantages over the cabinet; for example, they may be kept like books in a bookcase, the upright position rendering the contents less liable to the attacks of mites; they are more readily referred to, and are more portable, and they admit of our gradually expanding our collections to any extent. Cabinets, on the other hand, are preferred by many, for the reasons that they are compact and generally form a handsome article of furniture; moreover, good cabinets are made entirely of mahogany, which is the best wood for the purpose; deal, and other woods containing resinous matter, having a decidedly injurious effect on the specimens. As a preservative, there is, after all, perhaps nothing better than camphor; but it should be used sparingly, or its tendency will be to cause greasiness of the specimens.
V.
BEETLES.
By E. C. Rye, F.Z.S., etc.
The general rules, so ably expounded by Dr. Knaggs in his instructions for collecting _Lepidoptera_, as to constant alertness and making "the reason why" the starting-point of investigation, apply with equal force to the collector of _Coleoptera_, and need not be here recapitulated. But they do not, in the instance of the latter, require generally to be observed, except as to the perfect state of beetles; for, owing to the hidden earlier conditions of life of most of those insects, and to the long period during which these conditions exist, it is but seldom that the pursuit of rearing them, so universally and profitably adopted by the Lepidopterist, is found of much use to the collector of beetles. And this is very much to be regretted; because, in the majority of cases, if the latter succeed in rearing a beetle from its earliest stage, and keep proper notes of its appearance and habits, he will probably be adding to the general stock of knowledge, as the lives of comparatively few, even of the commonest species, are recorded from the beginning. It may be, also, in addition to the reasons above mentioned, for the usual want of success attending the rearing of beetle larvæ, that the fact of bred specimens being frequently (from the artificial conditions attending their development, and from their not being allowed that length of time which, in a state of nature, they require after their final change before they are ready to take an active part in their last stage of life) not nearly so good as those taken at large, militates considerably against the more general use of this method of adding to a collection. In this respect, of course, the Lepidopterist is actuated by precisely opposite motives; as for him, a bred specimen is immeasurably superior to one captured. And the fact of so few beetle larvæ being known at all, or, if known, only to the possessor of somewhat rare books, renders it very likely that a mere collector, finding a considerable expenditure of patience and trouble result in the rearing of a species of which he could at any time readily procure any number of specimens, may very probably abandon rearing for the future.
These observations, however, are not in the least intended to dissuade anyone from breeding or endeavouring to breed beetles. On the contrary, it is obvious from them that it is precisely by attending to these earlier stages that the earnest student (novice or expert) has the most chance of distinguishing himself, on account of the more open field for discovery. And in the instance of many small, and especially gregarious, beetles, breeding from the larvæ is frequently very easy, if only the substances (fungus, rotten wood, roots, stems of plants, &c.) containing them be carefully left in precisely the state as when found, and be exposed to the same atmospheric or other important conditions. In fact, to ensure success and good specimens, it is best that in their early stages beetles should be "let alone severely."
It may be here observed that we have been lately in this country indebted to the minute observations and great tact of some of our best students of _Micro-Lepidoptera_ (in which branch of entomology we are second to none in Europe) for some most interesting additions to our knowledge of habits, and for long series of beetles usually rare in collections.
Dismissing then the earlier stages of beetles, the following observations will apply only to the imago, or "beetle proper." And here I would repeat how evident it is that the knowledge of "the reason why" is especially indispensable to the beetle collector, judging from the extreme rarity of the occurrence of any new or valuable insect in the stores of a mere random collector or a beginner. For him, no old hand detects an equivalent to _Daplidice_ or _Lathonia_ in his duplicate boxes; whereas, among Lepidopterists, "school-boy's luck" is proverbial. I can give no reason for this statement, founded on my own (by no means trifling) experience in the way of examining specimens. And in this idea I think I am corroborated by the very great rarity in old collections and records of many species now universally common; the directions in older manuals, as to looking under stones, on walls, paths, &c., pretty clearly showing that the majority of captures in the olden time were what are now irreverently designed as "flukes." Still, it is astonishing to what good account a sharp observer may turn these casual meetings, often to him resulting in the discovery of "the reason why" as to the particular species accidentally found, and to the correlative increase of his collection. And, apart from captures during collecting expeditions, good things will at times occur to the alert entomologist: one, for instance, who will startle his friends in the streets by suddenly swooping with his hat after an atom flying in the sunshine, or who is not too proud to pick up another, racing on the hot pavement, during those days of early spring, when the insect myriads, revelling in warmth and light, after their long winters durance, may be seen madly dashing about, even in towns: on such a day, for instance, as that whereon a certain well-known doctor among the beetles found that living carabideous gem _Anchomenus sexpunctatus_, far from its native _Sphagnum_ and heath, wandering on the flagstones of the W.C. district.
But, before referring to special modes of hunting, it may be as well to mention the _instrumenta belli_ required for the equipment of the Coleopterist in this country. These are but few, and of the simplest kind; indeed, in entomology, as in the gentle art of angling, it is often the most roughly accoutred that secures the best basket. The umbrella net, figured at p. 47, used both for beating into and sweeping, cannot be dispensed with, and a beating stick can be cut out of the nearest hedge. The net itself should be of fine "cheese cloth," or some strong fabric that allows the passage of air, but not of beetles; otherwise, if of too close a fibre, it is apt to "bag" with the inclosed air, and reject its contents during the operation of sweeping. The net being of course used with the right hand, its left top edge especially bears the brunt of the attendant friction, and gets soon worn; it is consequently advisable to have an outer strip of stout "leather-cloth" sewn strongly over the rim there for some little distance, extending that protection also to the right top edge, though not for so long a space. The curved handle of the stick should be sawn off as soon as possible; it frequently catches in the pockets of the sweeper, causing a jerk to the net, and dispersal of its contents. For a similar reason, the ferruled apex may well be removed. Some collectors keep the sharp cutting edge of the spring sides of the net uncovered, sewing the net itself to holes drilled at intervals on the lower side of the springs: a net of this kind cuts very close, and where there is much herbage soon gets full of fragments, taking a long time to examine. It will be found handy if the bag of the net be cut to a point from the front towards the handle side: this causes the contents to gravitate to the bottom, as far as possible from the point where the rim meets the substance swept.
A common umbrella (easily slung by a stout string over the back when not in use) is an admirable (some think, superior) substitute for this net, as it can be held up higher by the ferrule, and tall bushes and trees (of which the branches nearer the top are usually most productive) can be beaten into it with more certainty of their beetle contents being caught. The steel frames will be found in the way when the beetles are being bottled; consequently, a good large gingham may be consecrated to collecting, and its inside (not merely the outer ribs) covered all over up to the middle (leaving no aperture there if possible) with thin white calico, stitched _over_ the frame.
Another good form of net for sweeping or dragging in long grass or herbage, is of the common fishing landing-net description, made of very stout wrought-iron or steel wire, either in a simple hoop, if a moderate size only be required, or with a single hinge to fold into two, or with three such hinges, folding into four, as may be desired. I have used one of these four-folding nets for years, and never found it fail. One end is hammered out flat and perforated, the other forming a male screw (1-1/2 inch long), bent at right angles with the body of the frame, passes through the hole, and fits into a female screw in a strong and long ferrule, fixed in the usual way to the end of a stout oaken walking-stick. As the power exerted in sweeping with such a net is great, and the action continuous, the simple screw is not enough, and a small screw hole is drilled right through the ferrule and the screw end of the net; a small thumb-screw, in shape like an old-fashioned clock key, going transversely through both, and effectually hindering lateral displacement. The framework of the net and the ferrule are better made of the same metal, because, if made of two metals of different density, the stronger soon wears away the weaker; and the stick must be inserted deeply into the ferrule, and held on with _two_ deep pins or small screws on opposite sides (not on the same level, however, as the wood is in that case weakened), one being insufficient to stand the strain. The net, of the same substance as that above mentioned, is made with a loose "hem" to slip on the frame before screwing it in the ferrule. A leather-cloth edging all round is advisable, and the bag should be cut long enough to prevent the possibility of the contents jerking out. Another very good plan for securing the frame to the ferrule is to have both ends of it soldered together into a deep square-sided plug, fitting into a corresponding square hole in the ferrule. The small cross-screw or pin is here also to be used; but the angles of the plug naturally keep a much tighter hold than the worm of a screw. Such a frame as this cannot, of course, be folded.
For water beetles, a similar net to that last mentioned is effective, but it should be stouter and with a flat front, for dredging closely against the sides and bottoms of ponds. The best substance for its bag is fine sampler canvas; and a very large, stout bamboo cane is at once light and strong for its stick. To avoid friction the bag may be affixed to small wire rings let into holes on the lower edge of the frame, or running on the frame itself.
A sieve is one of the most remunerative implements, and may be procured either simple or folding. It consists of a stout wire-framed circle, connected by a strong linen band, six inches deep, with the bottom of an ordinary wire sieve, the meshes of which are wide enough to allow any beetle to pass through. Leaves, grass, flood refuse, ants' nests materials, cut grass, seaweed, haystack and other _débris_, are roughly shaken in this over a sheet of brown paper, which should invariably form part of a Coleopterist's apparatus. A stout piece of double waterproof material may be substituted; and, in marsh collecting, must be used as a kneeling pad.
For ordinary bark collecting, a strong ripping chisel (of which the blade is well collared, so as not to slip) is as useful a tool as can be procured; but for _real_ tree working, no ordinarily portable instrument is thoroughly effective. Light steel hammers with a lever spike may delude the collector; but a woodman's axe, a saw, a pickaxe or crowbar, will often be found not too strong. For cutting tufts, &c., a strong garden pruning-knife is good, and an old fixed-handled dinner-knife (carried in a sheath) better. For holding the results of the operation of these instruments, the collector needs but one or two collecting bottles--one rather small and circular, of as clear and strong glass (_not_ cast) as can be got, with a wide mouth and flat bottom. Its neck should not slope, but be of even width, or the cork will often get out of itself. This cork should be a deep one, and be perforated longitudinally by a stout and large round quill, the bottom of which should be level with the bottom of the cork, the top projecting some inch and a half, with the upper orifice not cut off straight, but slightly sloped diagonally, so as more easily to scoop up beetles from the net or hand. It is closed with an _accurately fitting_, soft, wooden plug, rather longer than the quill, reaching exactly to the bottom of it, but with its top projecting above the top of the quill, and broader than it, so as to be easily pulled out by the teeth when the hands are occupied. The bottle should be secured by stout twine to the buttonhole, enough play being left for it to reach the net in any ordinary position. I usually secure the external junction of quill and cork with red sealing-wax, and have more than once found the bright red catch my eye when I have lost my bottle. [N.B. This loss will always happen to every collector; generally after a peculiarly lucky day's work: so use the string-preventive.] The body of the bottle may usefully be half covered with white paper gummed on. A few stout, plain glass tubes, papered in like way, and with plain corks, should be carried for special captures; and a cyanide bottle,[E] as mentioned at p. 57, or one containing bruised and shredded young laurel shoots, will be found useful for safely bringing home larger species, or such as would devour their fellow-captives. When put into these, beetles almost instantly die and become rigid, needing a stay of two days or so to become relaxed, in which condition they will then safely remain for a considerable period. In the first collecting bottle a piece of muslin should be put, to give the contents foothold: these are brought home alive, and killed by bodily immersion in boiling water, after which they are placed on blotting paper to drain off superfluous moisture.
[E] "Killing bottles," containing cyanide of potassium under a layer of gypsum, may be bought at most natural-history apparatus dealers, and are useful as relaxing dépôts.
Good things should always, when practicable, be set out at once, as the pubescence is apt to get matted if they are consigned for too long a period to the laurel or cyanide bottle; but such as remain unmounted can be put in a little muslin bag, and deposited in laurel until a more convenient opportunity. Beetles also, when taken in large numbers during an expedition into a productive locality, may be collected indiscriminately into a bottle containing sawdust (sifted to get rid both of large pieces and actual dust), slightly alcoholized, or with a small quantity of carbolic acid or cyanide of potassium in it. Each night, on reaching home, these will be found to be dead, and they can then be transferred to a larger bottle or air-tight tin can, partially filled with the same materials and a little carbolic acid to check undue moisture. Filled up with sawdust, this will travel in safety for any distance, and almost any time.
Species of moderate size, say up to that of an ordinary _Harpalus_, are in this country usually mounted on card. Much is to be said both for and against this practice: it enables the proportions and formation of limbs to be well appreciated, and it preserves the specimens securely; but there can be no doubt that it prevents an inspection of the under side, except at the slight trouble of extra manipulation in floating off in cold water and reversing, and that the gum used clogs the smaller portions of the insect that come in contact with it. Specimens larger than those mentioned should be pinned through the centre of the upper third of the right wing-case (never through the scutellum or thorax), and the limbs extended in position with pins on a setting board, made of a flat strip of cork glued on deal. Both these and the mounted examples must be left to dry, for a week at least, in the open air: if the boards are fitted in a frame, they can be reversed (as soon as the gum is dry in mounted specimens), so that the specimens are bottom upwards--dust cannot then collect on them, and there is less chance of mites attacking them. Specimens dry more rapidly in spring and summer than at any other time, and of course more readily in dry weather.
For mounting specimens, five or six small pieces of the finest and most transparent gum tragacanth, or "gum dragon," with rather less than the same number of pieces of clear gum arabic, are to be put in a wide-mouthed bottle with about a large wine-glassful of cold water. In a short time (twenty-four hours at most) the gum absorbs the fluid and swells; then add half as much more water, and stir the mixture, which, on being left for another twenty-four hours at most, will be ready for use. The mixture should be dull white, of even texture, and not quite fluid. Never make a large quantity at one time, or be persuaded to put _anything_ else into it. Card for mounting should be the whitest, smoothest, and best that can be procured. "Four-sheet Bristol board" for large specimens, and three-sheet for ordinary use, are about the proper degrees of thickness. Robersons, of Long Acre, artists' colourmen, have promised the writer to turn out cardboard of this kind with an extra milling, to ensure a good surface. Upon strips of this card, pinned on a setting board, the insects to be set out are mounted, one at a time, and not too close to each other, each on a separate "dab" of the gum, the limbs being duly set out with a fine pin or needle mounted in a paint-brush stick. A pin with the point very finely turned, so as to form a minute hook, is very useful; and for extremely minute work a "bead-needle" is valuable. The gum-brush should not be used in setting, but one or two very fine-pointed camel's-hair brushes may be found of advantage. Before mounting, reverse the specimen on the blotting-paper, and brush out its limbs as far as practicable with a damp flat brush. Very refractory individuals may require to be gummed on their backs; as soon as the gum is dry, their limbs can be more easily got into position, and they can then be gently damped off their temporary mount, and treated as above.
A small pair of brass microscope-forceps, ground or cut to a minute point, will often materially assist in getting refractory limbs into position. French white liquid glue (not made of shell-lac) is useful for fastening down larger specimens, as it is very strong and dries readily; and with a very small quantity of it rows of specimens can quickly and securely be roughly mounted, in the Continental way, which is preferable in many cases to leaving the insects for a long time in laurel before setting them out. Such specimens can afterwards, if desired, be relaxed by leaving them on damp sand, or in the cyanide or laurel bottle, and be then set in the way above indicated.
Care must be taken, in setting, not to put the specimen lop-sided on the card, or to distort its segments unnaturally by pulling them out of position, &c., and not to allow gum to lodge anywhere on the upper surface. It is easy, soon after a specimen is securely mounted, to remove with clean water and brush any superfluous gum. In preparing such insects as are liable to "run up" in drying (e.g. the _Staphylinidæ_), the abdomen should be duly pulled out by a bead-needle inserted at its apex; and to prevent the contraction of the internal muscles in drying, this part may be held with the liquid glue above mentioned. Usually, by putting these insects as soon as mounted into a box and keeping it closed for a few hours, while the first drying takes place, the proper dimensions of the abdomen may be preserved, and thus the natural facies of the insect retained. The contents of the bodies of very large insects may well be removed, either by the anal orifice, or by an incision on the lower side of the abdomen. The Oil-beetles (_Meloë_) alone require careful stuffing. This is best done by separating the entire abdomen from the metathorax, beneath the elytra, and close to their point of insertion: the body is then easily emptied and washed out, and may be filled with cut-up wool, which packs closely; when gummed on again, the junction is not visible, and the entire insect preserves its wonderfully obese appearance.
To save time, in mounting many specimens, it is better to merely gum straight on the strip of card as many specimens as can be managed at a sitting. The left side of each of these can then be slightly damped with clear cold water, and its left limbs set out: when all are thus done, the first one will be nearly, if not quite, ready to have its right side treated in like manner; and so on to the end. Very refractory specimens will sometimes require to be even held down with little braces of card on pins, and to have each limb damped and set out by a separate operation. The card of large specimens will often curl upwards in drying, owing to the amount of damp: to counteract this, the lower face of the card may be washed with a wet brush, just before gumming its surface.
Before putting insects away, when dry, the individual specimens should be cut off the strips of card by a straight cut on each side, one at right angles to the sides in front, and another behind, all (except the last) close to the tips of the limbs as set out, so that the whole card forms a parallelogram. A very little practice will enable the operator to do this both certainly and quickly. No two individuals (save perhaps a male and female, of whose sexual relations there can be no doubt, or an example mounted on its back, to show its under side, along with a member of the same species) should be allowed to continue on one card; much less should a row be left together. The reason of this is, that in many cases species closely resembling each other often get confused; and it is, moreover, difficult to get a glass of anything but a very low power to bear upon all parts of the individuals without injuring some of them. Each specimen should have sufficient card left _behind_ it to allow of a glass of high power being passed between it everywhere and its pin. The pin should perforate the card in the middle of, and close to, its hinder margin; and the whole card be lifted three-fourths up the pin, to keep it from mites and dirt as much as possible. Proper entomological pins can be obtained of all sizes at the agents of Edelsten, 17, Silver Street, St. Martin's-le-Grand; also (with all other apparatus) of any natural-history agent or dealer in London; such as Mr. E. W. Janson, 28, Museum Street, or Cooke, New Oxford Street. "No. 8" pin is, perhaps, the most useful size. In removing many specimens, proper insect forceps will be found handy: these can be obtained at the two last addresses; or of Buck, cutler, Tottenham Court Road.
Specimens will occasionally become discoloured with grease, usually from defective drying, though many water beetles and internal feeders, and most autumn-caught specimens, are specially liable to this defect. Benzine is an effectual remedy for it and for mites, and can be liberally applied with a brush. Carbolic or phænic acid, dissolved in that fluid (or alone, see p. 64), is an effectual safeguard against mould from damp; and when in solution with water, this acid has been found useful as a wash for card and boxes, which then are not attacked by mites. To re-card a specimen that has become discoloured (whether from either of these causes, or from age), it is only necessary that it should be floated in cold water for a few minutes; the insect can then be dried, well saturated with benzine, and again mounted, looking as fresh as ever. But, in re-carding specimens, it is necessary to be very careful with such as were originally kept too long in a laurel or cyanide bottle, as they are apt to become so rotten that a little damp will cause a "solution of continuity."
As to storing the specimens when quite dry, I can add nothing to the excellent observations of Dr. Knaggs, at p. 65; the same remarks applying with equal force to _Coleoptera_; except, perhaps, that, even when the collector has (and is satisfied with) a cabinet, he is likely, in proportion to the _real_ work done by him, to establish type-boxes of all the difficult groups.
For the examination of insects, readily manipulated by being pinned singly on a square, flat, thick piece of cork or bung, a pocket glass is, of course, necessary. In this case, the best instrument is the cheapest in the long run, whatever its cost; and one by a good maker, such as Ross, with modifications of four powers, will suffice for any ordinary work. For very small species, a Coddington, of the clearest definition and highest power attainable, is of immense help. But when the collector finds that he needs a compound microscope to separate species, it is the firm opinion of the present writer that that collector had better take to some other pursuit than studying _Coleoptera_. To anyone, however, whose researches entail an examination of the minute cibarian and other organs of beetles, whether for purposes of classification or otherwise, the compound is absolutely necessary; though even then the lower powers are usually sufficient. For rough dissection, all that is needed are an oculist's very small lance-headed dissecting-knife and a stout and fine needle. With these, under a lens mounted on a little stage to allow the free use of both hands, much may be done. The writer, however, has seen and used a very pretty (and comparatively inexpensive) dissecting-stand, with various powers and much latitude of motion, by Ross.
After mentioning that, in sending mounted beetles by post to correspondents, it is far more practical to use a _strong_ box, not too deep, to fasten the pins securely, with a layer of manufactured wool in the lid (glazed side towards the beetles, so as not to catch limbs), and to put more wool outside, and write the address and affix the stamp on a label attached, than it is to pack carelessly, write "With care" outside,[F] and then grumble at the post-office because the insects are broken,--I think I cannot, with use, say anything more upon beetles in their preserved condition; and I will therefore now give some hints as to their haunts when alive.
[F] It is, however, always as well to write "Insects," signifying contents that are "caviare to the million," and therefore not likely to be appropriated en route.
To exhaust the accidental-capture system above alluded to, mention must first be made of sand-pit collecting, a most profitable employment, especially in spring and early summer. A clean, straight-sided silver-sand pit is the best, and if in or near a wood its attractions will be at their highest. Beetles, flying of an evening and by night, dash against the pit sides and fall to the bottom; others merely crawl in for shelter, or tumble over the sides, and many seem attracted by the mere damp at the bottom or in the corners. Old collectors used to recommend a sheet spread out to attract insects; and there is no doubt that a certain number can be found by such means, just as they can be picked up floating on horse-troughs or on ponds. Artificial traps exist in the corridors of the Crystal Palace, some half-inclosed country railway stations, and such places; crawling up the windows of which many specimens are to be found. But these can only be considered as indications of what species occur in the district, as they are mere stragglers. Deliberately laying traps in sand pits, on commons, &c., will be found most productive. Small dead animals, fir branches, dead leaves, &c., can be examined time after time with profit in such situations. Burying a stout branch with the bark on, leaving the top above the soil, and periodically examining it when damp and nearly rotten, has been found effective; many insects collecting beneath the loose wet bark.
After heavy floods, as during severe droughts, beetles may be found in great profusion; in the former case, by sifting the refuse left by the water; in the latter, by diligently examining the damp residuum of former ponds, and if no damp be found, by even searching below the surface where it last occurred.
The wet hay, often decayed and mouldy, at the bottoms of stacks, which bad farmers have placed directly on the ground, will be found to teem with beetle-life; as will the margins of dung and vegetable-refuse heaps, wood-stacks, cut grass, &c.; and many good things may be taken by gently waving a light gauze net to and fro, just before sunset, close to such places, whither the instinct of nature impels the flight of myriads.
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Notes on Collecting and Preserving Natural-History ObjectsChapter XIV: Seaweeds, by W. H. Grattann 195 (2)
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