. Bulletin - United States National Museum. Science. COLLECTING AND PRESERVING INSECTS BANKS. 57 but the points are usually much better when cut by the scissors Seven to 8 mm. is a standard length used by the majority of col- lectors. Different insects require a different width at tip, and this is readily gauged by one in cutting them with the shears. These points should be of very stiff paper, or ;i thin cardboard of such texture that they will not readily bend, yet not too stiff for a No. 2 pin. A bright pin, No. 2, 35 mm., is pushed through the broad end of the point, and the insect is fast
. Bulletin - United States National Museum. Science. COLLECTING AND PRESERVING INSECTS BANKS. 57 but the points are usually much better when cut by the scissors Seven to 8 mm. is a standard length used by the majority of col- lectors. Different insects require a different width at tip, and this is readily gauged by one in cutting them with the shears. These points should be of very stiff paper, or ;i thin cardboard of such texture that they will not readily bend, yet not too stiff for a No. 2 pin. A bright pin, No. 2, 35 mm., is pushed through the broad end of the point, and the insect is fastened to the tip of the point by a little gum shellac, or gum tragaeanth, or even a good quality of glue. The shellac should be dissolved in pure alcohol, and this requires some time. If there is much water in the alcohol the gum will not dissolve properly. Gum tragaeanth is dissolved in water. A drop of corrosive sublimate or spirits of camphor added to the water will prevent the gum from souring. Mr. Dury recommends the following glue: One-quarter ounce gum arabic, one-eighth ounce gum traga- eanth, dissolve in hot water, and to this add one-half teaspoonful of glycerine and 4 drops of carbolic acid. Shellac has an advantage over most glues in that it requires but a very small amount to hold an insect. The insect should be mounted so that when the point is directed to the left the head of the insect is away from the person. The point should hardly be as high up on the pin as is a speci- men. In the case of Coleoptera and many Hemiptera and Hymenoptera, the insect is mounted with its back uppermost, but with fig'. 101.âmethod of glu- many Hvnienoptera and with some flies the ING BEETLE ON PAPER â POINT. back should be outward. The shape of the insect will be the guide in this matter. For many Coleoptera it is well to depress the tip of the point slightly so that it will fit to the insect. The idea should be to obscure as little of the insect as possible. In figure 101 one see
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