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.— method of glu- 

 many Hvnienoptera and with some flies the ING BEETLE ON PAPER 



■ 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 sees how the point should attach to 

 the insect and yet leave the insect readily observable from beneath. 

 The beginner is apt to use too much glue or shellac, but by practice 

 one can get expert in this matter and increase the neatness as well 

 as the value of the collection. 



When mounting up a large number of specimens, put shellac on a 

 few points only at a time. It is handiest, at least with beetles, to lay 

 the insects upon their backs, and then with the point dipped in shellac 

 pick up the specimen; then, when upright, press on the specimen 

 slightly to fasten it securely to the point. With insects having 

 long legs one may pick them up by a fine forceps and place them on 

 the point; then, by use of a lens, arrange them properly on the tip. 



