Fig. 2. Racks for holding storage vials. A., wooden block. B., cardboard "egg-box." C., "M.C.Z." rack position so that the liquid does not touch the stoppers constantly. Prolonged contact with alcohol hastens the deterioration of rubber and shrinks cork, allowing the liquid to escape. Tall slender bottles readily become upset or disarranged. Avoid this by keeping them in racks or trays. Fig. 2. shows several kinds of racks which you can easily make for yourself. "A" is a piece of one-inch plank in which have been bored neat rows of holes a little larger in diameter than the largest bottle which they may be expected to receive. These holes are closed at the bottom by a thin piece of wood or a sheet of cardboard, fastened to the block with glue and tacks. "B" is a box divided into bottle-size compartments by cardboard partitions like those of an egg crate. The racks, like the bottles, should be of one design throughout the collection. In size they may vary, but they should all be made in multiples of a basic set of measurements, so that they will fit together without waste of space. Arrange the bottles in the trays, and the trays upon shelves, in some orderly manner; perhaps in the sequence followed by the author of the book which you use to identify the animals. You will then be able to find, without trouble, any species which is represented in your collection. By preference, the shelves should be enclosed in a closet or cabinet. It is no small chore to dust a collection of bottled arthropods. "C" in Fig. 2. is an "M.C.Z." rack, used by the Museum of Comparative Zoology at Harvard. One side of the narrow box-like tray consists of a heavy Fig. 3. American Museum method of storing an alcoholic collection. 3