is saturated, a sudden decrease in temperature will result in the condensation of water. To prevent the drops which form on the underside of the lid from falling on the specimens, upholster the lid with cloth, or place a paper towel across the mouth of the vessel before putting on the cover. Fig. 4 is a diagram of a relaxing box. When softening specimens which have been stored between layers of cotton or wrapped in paper enve- lopes or tubes, do not attempt to unwrap them. Put them into the box packing and all. The relaxing box should not be filled to the top, since the moisture penetrates so great a mass slowly, and the outer specimens might fall apart before the inner ones are relaxed. However, several loose layers of wrapped specimens can safely be placed in the relaxing box at one time. The time required to relax the specimens varies with their size, the amount and nature of the packing, and the temperature. In general, for very small or delicate species overnight will be long enough. Twenty-four hours is sufficient for most insects, but a few very large kinds may take longer, especially if the wings are to be spread as described in leaflet number 5. If it is not possible to finish mounting a box full of insects at a sitting, the remainder may usually be left over till the next day without damage, but over-long exposure will result in discoloration of some species and eventually in disintegration of the specimens. of the time. When less than four labels are required, your choice of holes will be influenced by the number and nature of the labels, and by the thickness of the specimen. 10. A relaxing box. This is a humidor used to soften specimens which have been dried for storage or to keep fresh specimens in workable condition until wanted. It is a large- mouthed, moderately shallow, watertight vessel with a close lid, large enough to contain a considerable number of insects in their storage packing if necessary. The museum relaxing boxes were made of sheet copper by a tinsmith, and measure 14" x 8" x 5". However, a tobacco tin, one pound or larger, is equally satisfactory while it lasts, and when rusted through can be easily replaced. An ice box storage jar or a small aquarium covered with a pane of glass will also do the job. In the bottom of the vessel should be about an inch and a half of some porous material capable of absorbing a great deal of water; sand, soft paper, balsa wood, plaster of paris, or a synthetic sponge, for instance. This is kept soaking wet while the box is in use. A layer of dry cotton batting about an inch thick on top of this blotter will preserve the specimens from damage through direct contact with the liquid. A tablespoonful of paradichlorobenzene moth crystals under the cotton will discourage the development of mold. Since the atmosphere inside the relaxing box Fig. 4. Diagrammatic vertical section of a relaxing box made of a tobacco tin. A. Soaking-wet blotting paper. B. Paradichlorobenzene moth crystals. C. Dry cotton. D. Insects wrapped in paper tubes. E. Paper towel. Fig. 5. A Cardboard storage box for insects. 3