This holder was devised and made to fill the want of a suitable piece of apparatus to hold a large number of cover-slips while staining. It consists of four upright brass posts rising from a flat, square base, each post being securely fastened in a corner of the base, and of some twenty or thirty square bands or hoops of brass fitting snugly around the four posts, part of one side of each band having been cut away. The base should project slightly beyond the four posts, so that the bands when placed over and around the posts will rest on it. Cover-slips, either singly or in pairs, with back to back, can be placed between each band, the corners of the cover-slips projecting between the posts. When in position the cover-slips are a sufficient distance apart to allow the stain to run in between them.
The various stains can