[a]Fig. 52.]—Method of folding paper for envelopes: first fold on line AB; then on AD and CB; then on BF and EA.
Mounting Butterflies.—When the collector has time enough at his disposal he should at once mount his specimens as they are intended to be displayed in the collection. We shall now proceed to explain the manner in which this is most advantageously accomplished. The insect should first of all be pinned. The pin should be thrust perpendicularly through the thorax, midway between the wings, and at a considerable elevation upon the pin. It should then be placed upon the setting-board or setting-block. Setting-boards or setting-blocks are pieces of wood having a groove on the upper surface of sufficient depth to accommodate the body of the insect and to permit the wings to be brought to the level of the upper surface of the board (Fig. 53). They should also be provided either with a cleft or a hole which will permit the pin to be thrust down below the body of the insect for a considerable distance. As a rule, the wings of all specimens should be mounted at a uniform elevation of about seven eighths of an inch above the point of the pin. This is known as the "continental method" of mounting, and is infinitely preferable to the old-fashioned "English method," in which the insect was pinned low down upon the pin, so that its wings touched the surface of the box.
[a]Fig. 53.]—Setting-board designed by the author. The wings of the insect are held in place by strips of tracing-muslin, such as is used by engineers. The grooves at the side serve to hold the board in place in the drying-box. (See Fig. 59.)
[a]Fig. 54.]—Setting-block: A, holes to enable the pin to reach to the cork; C, cork, filling groove on the bottom of the block; B, slit to hold thread.
[a]Fig. 55.]—Setting-block with butterfly expanded upon it.
Setting-blocks are most advantageously employed in setting small species, especially the Hesperiidæ, the wings of which are refractory. When the insect has been pinned upon the setting-board or setting-block, the next step is to set the wings in the position which they are to maintain when the specimen is thoroughly dry. This is accomplished by means of what are known as "setting-needles" (Fig. 56). Setting-needles may be easily made by simply sticking ordinary needles into wooden matches from which the tips have been removed. In drawing the wings into position, care should be taken to plant the setting-needle behind the strong nervure on the costal margin of the wing; otherwise the wings are liable to be torn and disfigured. The rule in setting lepidoptera is to draw the anterior wing forward in such a manner that the posterior margin of this wing is at right angles to the axis of the body, the axis of the body being a line drawn through the head to the extremity of the abdomen. The hind wing should then be moved forward, its anterior margin lying under the opposing margin of the front wing. When the wings have thus been adjusted into the position which they are to occupy, slips of tracing-muslin or of paper should be drawn down over them and securely pinned, the setting-needles being removed.