Directions for Collecting and Preserving Insects. Charles V. Riley

Directions for Collecting and Preserving Insects - Charles V. Riley


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The knapsack may be made on the plan of a cartridge box, of stout canvas or leather, and should be of moderate size and slung onto the belt so as to be slipped to any part of the waist and not hinder free bodily motion. It may be used to carry bottles, phials, and other small appliances, and should be accordingly partitioned and furnished with loops or pockets on the inside. The cigar-box is for the reception of pinned specimens, and may be slipped onto the belt, or buttoned to the trousers by means of leather.

      Fig. 44.—The Butterfly net-frame.

      “The greatest requisites in collecting are a pair of sharp eyes and ready hands, with coolness and self-possession; but a few traps will materially aid. One of the most important is the hand-net, which may be made so as to subserve the two purposes of a sweeping and an air-net.”

      “The frame of the net which I use is illustrated herewith (see Fig. 44), and will be found strong and serviceable and conveniently portable. It is constructed as follows: Take two pieces of stout brass wire, each about 20 inches long; bend them half-circularly and at one end by a folding hinge having a check on one side, b. The other ends are bent and beaten into two square sockets, f, which fit to a nut sunk and soldered into one end of a brass tube, d. When so fitted, they are secured by a large-headed screw, e, threaded to fit into the nut-socket, and with a groove wide enough to receive the back of a common pocket-knife blade. The wire hoop is easily detached and folded, as at c, for convenient carriage; and the handle may be made of any desired length by cutting a stick and fitting it into the hollow tube a, which should be about 6 inches long. It is well to have two separate hoops, one of lighter wire, furnished with silk gauze or some other light material, for catching flying insects, and one which is stouter and furnished with a net of stronger material for sweeping non-flying specimens.

      “Another still more simple, but less convenient frame, is thus described by my friend F. G. Sanborn, of Boston, Mass.:

      Fig. 45.—The

       Sanborn net-frame.

      ‘Make a loop of strong iron or brass wire, of about 3–16ths of an inch in thickness, so that the diameter of the loop or circle will not exceed 12 inches, leaving an inch to an inch and a half of wire at each end bent at nearly right angles. Bind the two extremities of the wire together with smaller wire (see Fig. 45, a), and tin them by applying a drop of muriate of zinc, then holding it in the fire or over a gas flame until nearly red hot, when a few grains of block tin or soft solder placed upon them will flow evenly over the whole surface and join them firmly together. Take a Maynard rifle cartridge tube, or other brass tube of similar dimensions; if the former, file off the closed end or perforate it for the admission of the wire, and having tinned it in the same manner on the inside, push a tight-fitting cork half way through (Fig. 45, c) and pour into it melted tin or soft solder, and insert the wires; if carefully done, you will have a firmly constructed and very durable foundation for a collecting net. The cork being extracted will leave a convenient socket for inserting a stick or walking cane to serve as a handle.’

      “My friend, J. A. Lintner, of Albany, N. Y., makes very good use, in his ordinary promenades, of a telescopic fish-rod, with a head (Fig. 46) screwed on to one end, in which to fasten an elastic brass coil on which the net is drawn, but which when not in use sits snugly inside his silk hat.

      Fig. 46.—

       Clamp of the

       Lintner net.

      “The bag should taper to the bottom, and in any case its length should be fully twice the diameter of the hoop, so that by giving the net a twist, the mouth may be closed and the contents thus secured. The sweeping-net may be protected around the hoop with leather, and in use should be kept in a steady and continued back-and-forth motion, over and touching the plants, until the contents are to be examined; when, by placing the head at the opening and quietly surveying the restless inmates, the desiderata may be secured and the rest turned out. A sudden dash of the air-net will usually lay any flying object at the bottom. A net for aquatic insects may be made on the same principle, but should be stout, with the meshes open enough to allow free passage of water, and the bag not quite as deep as the diameter of the hoop. A forceps net, which consists of two gauze or bobbinet covered frames, having riveted handles, so as to close like a pair of scissors, is employed for small insects; but I find little use for it. A coarse sieve, together with a white towel or sheet, will be found of great service for special occasions, particularly in the spring, when the search for minute insects found under old leaves, or for pupæ around the butts of trees, is contemplated. With the sheet spread on the ground, and a few handfuls of leaves and leafy mold sifted over it, many a minute specimen will be separated from the coarser particles and drop to the sheet, where the eye may readily detect it. Conversely, the earth taken from around trees may be sifted so as to leave in the sieve such larger objects as pupæ, etc. Another favorite plan, with some collectors, of obtaining specimens, especially night-flying moths, is by ‘sugaring.’ This consists of applying to the trunks of trees or to strips of cloth attached to the trees some sweet, attractive, and stupefying preparation. Diluted molasses or dissolved brown sugar, mixed with rum or beer, is most frequently employed. I have found sugaring of little use till after the blossoming season, and it is almost impossible to so stupefy or intoxicate an insect that it will remain upon the sugared tree till the next morning. I generally sugar at eve, and visit the tree several times between sundown and midnight, armed with wide-mouthed killing-bottles and accompanied by a second person, who carries a dark-lantern. Isolated trees, on the edges of woods, give the best results. Everybody knows how some poor moths will persist in flitting around a light until they singe their wings; and, as many insects are strongly attracted to bright artificial light, it may be employed with good results, especially during warm and damp evenings. The collector should never go unprovided with a small box or tube full of different sized pins (a corked cartridge-tube makes a good box,) a pair or two of forceps, a pair of scissors, a little mucilage, and the killing apparatus to be described.”

      With these general remarks, it will be well to consider some of the important paraphernalia more in detail.

       Table of Contents

      The Sweeping Net.—A multitude of insects of all orders feed or rest on grasses and other low plants. Upon close inspection of these plants a careful observer will be able to secure, without any instruments, not only many mature insects, but also many larvæ in connection with their food-plants. This is laborious and slow work, only necessary on special occasions. The beating net, which is constructed on the same general plan as the butterfly net, is valuable here as a time saver. By holding the handle of the net firmly in one hand and quickly sweeping over the plants first from right to left, and then, after quickly turning the net again, sweeping from left to right, most insects coming within reach of the sweep will fall into the bag and may be easily taken out and put into the collecting-vials. From this mode of operation it is evident that the sweeping net must be stronger in all its parts than the butterfly net, but otherwise it may be made on the same plan.

see caption

      Fig. 47.—The Deyrolle Sweeping Net. a, net entire; b, frame; c and d, attachment of frame and handle (original).

      The ring should be rigid, made of brass or iron, either of one piece or of two pieces,


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