"A less commendable method of preserving larvæ is to place them in alcohol. The larvæ should be tied up in sacks of light gauze netting, and a label of tough paper, with the date and locality of capture, and the name, if known, written with a lead-pencil, should be attached to each such little sack. Do not use ink on labels to be immersed, but a hard lead-pencil. Alcoholic specimens are liable to become shriveled and discolored, and are not nearly as valuable as well-inflated and dried skins."
[Illustration FIG. 64.--Drying-oven: _a_, sliding door; _b_, lid; _c_, body of oven with glass sides; _d_, opening for inserting inflating-tube; _e_, copper bottom; _f_, spirit-lamp; _g_, base (Riley).]
"When the skins have been inflated they may be mounted readily by being placed upon wires wrapped with green silk, or upon annealed aluminium wire. The wires are bent and twisted together for a short distance and then made to diverge. The diverging ends are pressed together, a little shellac is placed upon their tips, and they are then inserted into the opening at the anal extremity of the larval skin. Upon the release of pressure they spread apart, and after the shellac has dried the skin is firmly held by them. They may then be attached to pins by simply twisting the free end of the wire about the pin, or they may be placed upon artificial imitations of the leaves and twigs of their appropriate food-plants."
THE PRESERVATION AND ARRANGEMENT OF COLLECTIONS
The secret of preserving collections of lepidoptera in beautiful condition is to exclude light, moisture, and insect pests. Light ultimately bleaches many species, moisture leads to mould and mildew, and insect pests devour the specimens. The main thing is therefore to have the receptacles in which the specimens are placed dark and as nearly as possible hermetically sealed and kept in a dry place. In order to accomplish this, various devices have been resorted to.
[Illustration FIG. 65.--Detail drawing of front of box, made to resemble a book: _s_, _s_, sides, made of two pieces of wood glued together across the grain; _t_, tongue; _g_, groove; _c_, cork; _p_, paper covering the cork.]
[Illustration FIG. 66.--Detail drawing of front of box: _t_, top; _b_, bottom; _e_, side; _f_, strip, nailed around inside as at _n_; _c_, cork; _p_, paper lining.]