How to Collect and Preserve Insects

by Herbert H. Ross

The following items are needed for the vial aspirator, [fig. 4]: a vial, 1¼ inches in diameter and 3 or more inches long, a two-hole rubber stopper with openings to fit one-fourth-inch diameter glass tubing, 16 inches of one-fourth-inch diameter glass tubing, rubber tubing 24 inches long to fit over the glass tubing, a small metal file (the triangular type is best), a small piece of cheesecloth, some string, and a bunsen burner. Construct the vial aspirator according to the following directions and as shown in [fig. 4].

1. Cut the glass tubing into three pieces, 3 inches, 8 inches, and 5 inches in length. To cut the tubing, score it with an edge of the metal file; then hold the tubing with both hands so that the thumb of each hand is on the side of the tubing opposite to the scored mark; break the tubing away from the body by exerting pressure with the thumbs.

2. Make a slight bend in the center of the 8-inch piece of tubing and a right angle bend in the 5-inch piece, as follows: hold one piece of glass tubing with both hands and place the center of it in the blue flame of the bunsen burner; rotate the tubing slowly. When the glass glows yellow, it begins to soften. Bend the tubing to the desired angle. Then quickly withdraw the tubing from the flame.

3. Heat one end of the 8-inch piece of glass tubing in the bunsen burner, slowly rotating the tubing so that the sharp edges melt slightly and round out; then allow the tubing to cool. Heat one end of the 3-inch tubing in the same manner. Smooth the remaining rough edges of the glass tubing by heating them slightly.

Fig. 4.—Vial type of aspirator or sucker. End g is placed in the mouth; c is used to pick up the insects. Shown also is a cyanide cork, h-i, which is used to kill insects in the aspirator.

Fig. 5.—Tubing type of aspirator. Parts for this aspirator should be compared with equivalent parts for the aspirator shown in [fig. 4]. Noted especially should be the position of the glass tube, c, and the length of the rubber tube, f.

4. Insert the 8-inch and 5-inch pieces of glass tubing into the rubber stopper. The longer piece, [fig. 4]c, should project about 1½ inches into the vial. The shorter piece, [fig. 4]d, should project about three-fourths inch.

5. Over one end of the 5-inch piece of glass tubing, [fig. 4]e, tie two thicknesses of cheesecloth securely with string.