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the habit of placing the wings in the form of a triangle when at rest, are slender-bodied, having the antennæ always simple. They are found also in woods, resting upon the under side of leaves. The leaf-rollers, Tortricida, are found very abundant in summer, upon leaves of trees, low bushes, and herbage. The larvæ live in rolled-up leaves. The Tineide, though the smallest moths of the order, are very destructive to vegetation. The wings are narrow and edged with delicate fringe. The clothes-moth and corn-moth are representatives of the family. They are found in a variety of situations; many fly in the grass, always alighting head downward. These, with Alucita, a small family with wings, divided into numerous branches, close the order.
HEMIPTERA. Bugs, locusts, plant-lice, &c.—This order has by some naturalists been divided into two, Heteroptera, or dissimilar winged insects, comprising the true plant bugs, and the Homoptera, or "insects with four wings of the same membranous texture, or having the upper pair leathery and the under pair membranous," as in the cicadas and leaf-hoppers. We will, however, consider them as one, and describe them as insects having a horny beak or sucking tube, four wings, the first pair of which are thick ened at the base and lie flat, or are uniform throughout, and sloping at the sides. The transformations are complete. Many of the species are aquatic; a few are wingless.
The insects are collected in the same manner as beetles; sweeping from grass and herbage, by shaking or beating, or by picking them from trees or plants on which they are found. They may be preserved in alcohol without injury. (The cicadas, as an exception, keep their colors better if killed by brushing with benzine.) The water net should be used for aquatic species, which live upon submerged plants and grasses. Those that remain torpid, or hybernate, may be found in stone walls, under rubbish heaps, and in dead wood, in all stages of their growth; brush heaps afford an excellent shelter. Specimens should be pinned through the triangular scutellum in the middle of the body; smaller hard species may be placed on card slips described for coleoptera.
The harvest flies, or Cicadas, are very plentiful upon the trees during warm weather; the males may be discovered by their noisy song, which is produced by a drum-like apparatus under the wings on the last seg. ment of the thorax. The seventeen-year locusts belong to this family. The tree-hoppers, Membracididae, differ much in the shape of the thorax, produeing many odd forms. They are found in great numbers on the leaves and limbs of trees, or on the stems of plants. The leaf-hoppers, Tettigoniade, pass their lives on the leaves of plants, where they may be collected late in summer in abundance. Aphide, or plant-lice, live upon all parts of plants, sucking the sap and destroying all vitality. Some species are apterous. Being soft-bodied insects, they should be preserved in alcohol. The bark-lice, Coccidæ, commonly called scale insects, are found sticking closely to the bark of trees. As they are crushed by removal, it is best to take them with a small portion of the bark to which they are fastened. The young insects escape from beneath the parent shell in the spring. The water-boatmen, Notonectidæ, resemble the leafhoppers in shape, though they are larger, and have the legs formed for swimming. They may be taken with the water net. The Nepidæ, also aquatic, are very predaceous. Some of the species of Belostoma are nearly three inches long. The Hydrometrida, which are among the earliest spring insects, are seen running upon the surface of water. The Reduvius, or wheel-bug, is found in gardens, feeding voraciously upon caterpillars, and should be handled carefully, as the wound made by its piercer is quite as painful as the sting of the wasp. The family Reduviidæ are terrestrial. The Pentatomidce are a large family of brightly colored insects, generally oval in form, having a very large distinct scutellum or triangular piece at the base of the wings. They are found upon plants; many are of large size. The Corcidæ are found on the roots and stems of plants, and are very active, using both legs and wings to the best advantage. The squash-bug is an example. Many of the species are gaily colored. The bed-bug belongs to the Cimicidæ, which are generally wingless. Some of the family are parasites, living upon birds. The true-lice, Pediculi, are degraded forms of hemiptera, though still preserving the sucking tube. They are parasitic, upon man and other animals. The species of birçi-lice are very numerous, nearly every bird having its parasite.
Flies, gnats, &c., are provided with a kind of proboscis, and have but two wings, the second pair being reduced to a pair of small organs called balancers or poisers. Their transformations are complete. The larvæ are footless maggots. Pupa in some cases changes inside the skin of the larva. The limbs are free. Many species are aquatic.
In collecting diptera the sweep net is found to be most useful, and particularly in new localities. After several vigorous sweeps of the net right and left among grass, flowers, and herbage, says Loew, "by a dex. trous twist of the handle, the apex of the sack is thrown over the ring so as to prevent the escape of the insects, and give them time to compose themselves at the bottom. It is then opened, and the common species are allowed to pass; but if there is one that is desired, it is allowed to advance to the middle of the bag; and then it is gently grasped from the outside of the bag with the right hand. The other captures are driven down to the bottom by blowing moderately on them, and confined there by letting the ring fall over the right hand which holds the insect, that is now easily seized with the left hand.” When all the good things" are taken out, the bag is inverted and the sweeping continued.
A little instrument similar to Fig 10, copied from Newman's History of Insects," is useful for taking diptera or hymenoptera which alight on umbelliferous flowers. It consists of a scissor-like frame, with two circular or octag. onal rings, covered with silk gauze or Swiss muslin.
Many specimens can be obtained by breeding, and withi little trouble. Dipterous larvæ are found in dung, decayed wood of stumps, mold in hollow trees, soil under manure,
stems or stalks of plants, and weeds, toadstools, &c. Yir. 10. Many are found in water. They should be kept in glass jars or damp boxes, and not allowed to get too warm. Aquatic species can be kept in glass jars with vegetation enough to oxygenate the water. Where larvæ are known to transform at the place in which they are found, it is better to leave them till they may be taken in the pupa state.
Flies are injured by pressure, and therefore should be killed with fumes of benzine or ether, and then pinned, or pinned alive and placed in a box the bottom of which has been previously moistened with creosote. The very small or delicate species are sometimes transfixed upon fine silver wire and stuck into small pieces of pith through which common. sized pins are inserted, something after the manner of the card slips for
the coleoptera. In setting long-legged specimens, a square piece of stiff paper or card should be pushed up on the pins under the insect, and the legs allowed to rest upon it until thoroughly dry.
Musquitoes pass the first part of their lives in water, and may be seen by thousands in old rain-water barrels, jerking about when distarbel, or resting at the surface in order to obtain a fresh supply of air. They belong to the family Culicidæ. The crane-flies, Tipulida, are known by their long slender legs and bodies. The larvm are found both on land and in the water; some live under the bark of trees or in damp situations. Cecidomyia includes the gall-flies which do so much injury to growing grain. Those species injuring wheat may be collected by sweeping in the spring. The Mycetophilido are small, active insects found in damp places; some species enter our houses. The larvæ live in fungi or decay. ing vegetable matter. The insects comprising the family Stratiomyidce are prettily colored, and generally found upon flowers in damp situations. Some of the larvæ are found under ground, while others live in rotten wood, or are aquatic. Horse-flies, Tabanidæ, are among our largest dip. tera, and are found quite common in wood lands or pastures. The. troublesome little fly which buzzes unceasingly around one's head, when in the woods, belongs to this family. The bee-flies, Bombyliidæ, are to be met with in April and May, in sumy paths in woods. They fly swiftly, hovering at times over flowers, extracting the honey with their long slender suckers. The Asilidæ in the larval state live upon the roots of plants, preying upon other insects in the perfect state. The Syrphidee are beneficial, as the larvæ feed upon plant lice, They resemble hymenoptera in shape and color. Estridæ, or bot-flies, are parasitic upon herbivorus animals. The flies have thick, hairy bodies. The common house-fly belongs to a large family of insects (Muscida) which in the larval state are soft, footless grubs or maggots. Tachina is parasitic upon caterpillars, destroying great numbers of them. By collecting the flowers of Compositæ, and keeping them in boxes, many species may be obtained. The Hippoboscidæ, or spider-flies, are found upon birds and animals. Fleas are wingless flies. The different species ilibabit different animals.
Specimens should be arranged in tight drawers, or in boxes fitted with covers or glass slides, and kept in a case made for the purpose; or boxes can be made in the form of books, using both sides for specimens, and allowed to stand upon regular book shelves. A very convenient size of box is nine by thirteen inches outside measurement, and two and a half inches deep. All boxes should be lined with sheet cork, and then neatly papered inside with white paper, using starch paste. Cork strips, as well as entomological pins, can be obtained at any naturalist's establishment in the large cities. German pins are always the best to use. Numbers five and eleven (Carlsbad pins) answer for most insects; for small species, lower numbers are required. The specimens should always be pinned at the same height, as a lack of uniformity gives an idea of a lack of neatness. The specimens should be arranged from top to bottom in regular rows, three or four abreast, showing as many varieties as is practicable, and a neat label be placed above each. They should be numbered, and the number recorded in a catalogue, giving the name of the insect, locality where taken, number taken, by whom, and any notes connected with its capture, as well as the date. Where several insects of a species are taken at a time under the samo circumstances, or in the
same locality, one number may be used for all. Any blank book will do for a catalogue, ruling clear across the sheet, thus:
Disks of different-colored paper, quarter of an inch in diameter, or less, may be used to represent States or localities, and the catalogue number may be written upon these. They are easily made with a common harness punch. To produce greater variation, labels of two colors may be employed.
It is desirable to have both sexes represented in every species, and when they are taken together, if not pinned upon one pin, the fact should be noted on small labels, and placed upon each pin.
Specimens of natural history are liable to the attacks of a small beetle, Anthrenus destructor, which consumes the interior of dried specimens of insects, leaving the shells to fall to pieces when the case is opened, or slightly jarred. Their presence may be detected by fine dust in the bot. tom of the box, or by the shed skins of the larvæ which do the injury. Boxes should be kept tight, and it would be well to keep a piece of gum camphor in each, though it is not advisable to rely upon it alone. The insect is oval, grayish, marked or mottled with black; larva thickened in the center, tapering at each end, and covered with short, bristly hairs. The cabinet should be examined every few weeks, and, if the least dust is discovered under any insect, thoroughly treated with benzine and left tightly closed for several days. Poisonous solutions, as a general thing, do more injury to the insects than good, by gumming them up and spoiling their appearance. As cheap benzine is apt to have the same effect, only that which is most free from oil should be used. The interior of the bodies of large moths, particularly females with eggs, should be removed, and the space filled with cotton. This not only makes them much lighter, but prevents them from becoming greasy. Mold may be destroyed by brushing the insect with benzine to which a little creosote has been added. When dampness has caused the wings of butterflies or moths to droop, the insect may be relaxed by placing it on damp sand for a few hours, when it may easily be reset. Light should always be excluded, even when glass is used for covers.
Therefore, after a collection has been made, the greatest care must be taken to keep it in order, to guard it from injury and to preserve it in its original beauty, or it soon shows neglect, and is speedily ruined.
RECENT PROGRESS IN FISH CULTURE.
The artificial propagation of edible fishes, which is shown by experiments in every quarter to be practicable, and also in a high degree economical of the material of reproduction, is assuming national importance. Admitting that it may never become one of the great producing interests of the nation, it must be acknowledged that, while it furnishes instructive popular experiments in natural history, and gratifies and educates a natural taste for rural pursuits, it undoubtedly adds to the luxuries of generous tables, and increases in some degree the food supplies of the people. That public fisheries can be improved by artificial means, at smallexpense, may be established by undoubted proof; and that he who accomplishes such a result is a public benefactor, will be readily admitted. If, as science asserts, a fish diet is a fortifier of the brain, who needs it more than the restless, rushing, irrepressible American ?
FISH CULTURE NO NOVELTY.
The Chinese, who keep a constant supply of fish in their rivers and canals, notwithstanding the unexampled density of their population, have practiced fish-hatching successfully for centuries. Fish are there so cheap that a penny will buy enough for a breakfast for a small family. An ingenious method of artificial hatching has been adopted, which is worthy of mention, at least as a novelty. The business of collecting and hatching the spawn for the supply of owners of private ponds is extensive. When the season for hatching arrives, the operators empty hens' eggs by means of small openings, sucking out the natural contents and substituting the ova. The eggs are placed for a few days under a hen. Removing the eggs, the contents are placed in water warmed by the heat of the sun, the eggs soon burst, and the young are shortly able to be removed to waters intended for rearing them.
The Romans were adepts at fish culture. Sergius Orata, who is reported as the originator of artificial oyster beds, grew them by millions in great reservoirs at Baia, on the Lucrine Sea, and built a palace near for convenience in serving his famous oyster suppers. Lucullus is said to have sold his stock of fish at £35,000. Some epicures nourished pet breeds of fish, as cattle breeders perfect particular strains of blood.
WHAT HAS BEEN ACCOMPLISHED IN EUROPE. France, England, Scotland, and Ireland, among other European states, are enjoying a manifest increase of fish supplies from artificial propagation. Many curious facts have demonstrated the feasibility of restocking the salmon rivers. Loch Shin, a lake of the Sutherland Mountains, in Scotland, having as an outlet the salmon river Shin, is fed by four rivers, the Terry, Fiack, Garvie, and Curry, which, prior to 1836, contained no salmon. In that year fish of the outlet river were conveyed in their spawning season to these streams, and ever since their progeny have passed through the lake to their native waters.
The Tay of Scotland, in which salmon, formerly abundant, became nearly extinct, has now a plentiful supply, through the efforts of the