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Photographed from exhibit in Brooklyn Museum of Arts and Sciences, by A. E. Rueff.

ANIMAL BIOLOGY

CHAPTER I

INSECTS

I. BUTTERFLIES AND MOTHS

1. Insect net. Since most butterflies and moths are more or less injurious, at least in their caterpillar stage, boys and girls should be taught that they are benefiting their community by catching and killing these insects in a painless manner. For this purpose an insect net and a poison bottle are necessary. An insect net may be made by securing a yard of galvanized iron wire (No. 3), bending it in the form of a ring (thus ?), and inserting the two ends of the wire in one end of a light wooden rod about three feet long. To the wire ring should be sewed a bag about two feet deep made of cheesecloth or bobinet (Fig. 1). To catch a butterfly or other insect, wait until it alights, then quickly place over it the opening of the net, holding up the closed end of the net till the insect flies to the top. Now place beneath the insect the open mouth of a poison bottle prepared as follows, and after the insect is in the bottle quickly replace the cover.

2. Poison bottle. Secure a pint fruit jar or a wide-mouthed bottle fitted with a cover. Into the bottom put a spoonful of more or less pulverized potassium cyanide. Thoroughly mix some plaster of Paris in water and thus make a thin paste. Carefully pour the liquid into the jar until it forms a layer about an inch thick. When this hardens, it covers and holds the cyanide in place, but it is porous enough to allow fumes to escape, which kill most insects in the closed space in a few moments. The bottles are perfectly safe in the hands of pupils. Care should be taken, however, not to handle the cyanide or to breathe in the fumes. The bottle

FIG. 1. Insect net.

tip of the pin into the

should be kept tightly closed when not in use, and should be distinctly labeled "Poison Bottle" (Fig. 2). If the bottle is broken, the pieces of glass and all the contents should be buried in the earth.

3. Preparation of butterflies for study or for collections. - For laboratory study it is desirable to use the largest butterflies obtainable. The work will be carried on to much better advantage if there is at least one mounted specimen for each two pupils. These should be prepared with the wings fully extended, with the legs spread out as in walking, and with the proboscis partly uncoiled. To get the material in this shape place two books about half an inch apart on a soft board; run an insect pin through the thorax of a freshly killed insect, extend the legs

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and proboscis,
then put the
body of the
insect between
the two books,
thrusting the
board beneath.

Spread out the fore wings on the book covers so that their hind margins are at right angles to the thorax, pull the hind wings outward into their natural position when at rest, and hold the two pairs in place with pieces of glass till the specimen has dried. Butterfly spreading boards may be bought or made (Fig. 3).

FIG. 2. Poison bottle for killing insects.

Dry specimens may be relaxed by placing a quantity of sand or crumpled paper in a battery jar or other wide-mouthed receptacle that can be tightly covered. Wet the sand or paper thoroughly and then sprinkle over it a little dry sand or cover with blottingpaper.

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Put in the dried butterflies about twenty-four hours before they are to be spread, and cover the dish. If the relaxing jar is kept in a warm place, the process will be hastened, but care should be

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taken not to leave the insects in the moist chamber long enough for mold to grow upon them. It is of course better to mount the butterflies as soon as they are killed.

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4. Insect boxes. A box for displaying a butterfly for class study may be made as described below by any fourteen-year-old boy; these cases will preserve the insects from year to year, thus saving labor as well as insuring good material that pupils can examine from both sides. The boxes may likewise be used as cages for the study of the activities of live grasshoppers, caterpillars, or other insects. After butterflies have been studied they should be transferred to an insect case or other moth-proof box, a piece of cotton soaked in carbon bisulphide should be inserted, and the box kept tightly closed till the butterflies are again needed. “ Chiclet ” boxes, since they have glass covers, may be used for storing and displaying the insect collections that may be made by pupils. A layer of absorbent cotton over the bottom of the box makes a good background (Fig. 4).

To make the insect boxes, secure from a mill or a local carpenter strips of wood 24 inches wide and inch thick, with grooves inch wide and inch deep, cut a quarter of an inch from the two margins of one side. About 18 inches will be required for each box. For the sides saw up two pieces each 51⁄2 inches long, and for the ends the

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FIG. 4.-Insect collection. (Prepared by Kny-Scheerer Co. Photographed by E. R. Sanborn, N. Y. Zoological Park.)

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