glycerine, or two tablespoonfuls to a quart. Glycerine will keep the specimens pliant long after the alcohol has disappeared. Do not use it, however, if you handle your collection frequently. You cannot avoid spilling a little of the liquid as you work; and when the alcohol evaporates, the residue of glycerine on tools and hands is unpleasantly sticky. Whether killed with alcohol in the field or with hot water in the laboratory, fresh specimens are placed, at first, in a solution which is too weak to preserve them permanently. It will, however, begin the dehydration without distortion. When they are transferred to a stronger preservative a day or two later, the specimens will not shrink as much as they would have done if dropped directly into the concentrated solution. The more gradual this "stepping- up," the less the shape of the specimens will be affected. Some biological preparations require a long series of baths differing in concentration by as little as five percent, but for most insects and spiders, one step is probably enough. The smallest and juiciest species may be the better for two. The concentrations recommended for these purposes are listed in the dilution table above. If a bottle contains a large number of bulky specimens, change the final preserving fluid at least once, after an interval of several days, before storing the bottle away indefinitely. The body fluids of the animals may dilute the first alcohol bath below the 70% minimum effective for long term preservation. As often thereafter as the alcohol becomes discolored, replace it with a fresh supply. When collecting in a remote area, far removed from your base of operation, and with a limited supply of alcohol, changing the fluid within a few days will be impractical. In this case, it is better to collect into straight 95% alcohol, risking the distortion, than to chance losing the specimens through dilution of the preservative by body fluids. Replace the killing fluid with fresh alcohol of appropriate concentration as soon as opportunity arises. It is likely that each collecting bottle filled in the field will contain specimens of several species, and possibly of different dates or localities. Before these can be incorporated into a scientific collection, they must be sorted and separated, so that one bottle contains creatures of one species, date, and locality only. You can do this most conveniently while changing the alcohol for the last time. When sorting a collection, be sure that every bottle, whether containing a single specimen or a dozen, also contains a label giving the locality and date of capture and the name of the collector. Field notes relative to the animals may also be included, as well as the name of the species, if you know it. Write these labels with black waterproof India Ink, on hard but unglazed paper of good quality. Make them of such size and shape that they fit into the bottles easily, and can be read conveniently through the glass. To assure the workmanlike neatness of your collection, use storage bottles of one shape and a few standard sizes. Two common kinds are shown in Fig. 1. The homeopathic vial, "A", is preferable for a large or little-worked collection, because the constricted neck grips the stopper tightly, retarding evaporation of the alcohol. The shell vial, "B", must be refilled more often, but its use in small muchhandled collections is justified by the ease with which the specimens may be extracted from it. Your local Fig. 1. Storage bottles for preserved specimens. A., homeopathic vials. Note tubes for minute specimens in the smaller. B., shell vials. druggist probably carries vials of these or other suitable shapes. If not, you can buy them in quantity from any scientific supply house. Four drams is the most generally useful size, while eight drams will accommodate the largest species which you are apt to catch in this part of the world (New York). Vials smaller than two drams dry out so quickly that they are a nuisance. If you are afraid of overlooking extremely minute specimens in a large container, store them in tiny tubes stoppered with cotton, putting these tubes into the vials of alcohol. Such tubes are shown in the smaller vial at "A" in Fig. 1. Rather than screw caps, bottles used for alcoholic specimens should have corks of the very finest quality. If the only available corks are coarse or faulty, use rubber stoppers. Store the bottles in an upright 2