A great difficulty is often experienced with microscopic fungi, such, for instance, as the _Sphæriacei_, in the necessity, whenever a new examination is required, to soak the specimen for some hours, and then transfer the fruit to a slide, before it can be compared with any newly-found specimen that has to be identified. To avoid this, mounted specimens ready for the microscope are an acquisition, and may be secured in the following manner. After the fungus has been soaked in water, where that is necessary, and the hymenium extracted on the point of a penknife, let it be transferred to the centre of a clean glass slide. A drop of glycerine is let fall upon this nucleus, then the covering glass placed over it. A slight pressure will flatten the object and expel all the superfluous glycerine around the edges of the covering glass. A spring clip holds the cover in position, whilst a camel-hair pencil is used to remove the glycerine which may have been expelled. This done, the edges of the cover may be fixed to the slide by painting round with gum-dammar dissolved in benzole. In from twelve to twenty-four hours the spring clip may be removed, and the mount placed in the cabinet. Glycerine is, perhaps, the best medium for mounting the majority of these objects, and when dammar and benzole are used for fixing, there is no difficulty experienced, as is the case with Canada balsam, if the superfluous glycerine is not wholly washed away. Specimens of _Puccinia_ mounted in this way when fresh gathered, and before any shrivelling had taken place, are as plump and natural in our cabinet as they were when collected six or seven years ago. Moulds are always troublesome to preserve in a herbarium in a state sufficiently perfect for reference after a few years. We have found it an excellent method to provide some thin plates of mica, the thinner the better, of a uniform size, say two inches square, or even less. Between two of these plates of mica enclose a fragment of the mould, taking care not to move one plate over the other after the mould is placed. Fix the plates by a clip, whilst strips of paper are gummed or pasted over the edges of the mica plates so as to hold them together. When dry, the clip may be removed, and the name written on the paper. These mounts may be put each in a small envelope, and fastened down in the herbarium. Whenever an examination is required, the object, being already dry-mounted, may at once be placed under the microscope. In this manner the mode of attachment of the spores can be seen, but if mounted in fluid they are at once detached; and if the moulds are only preserved in boxes, in the course of a short time nearly every spore will have fallen from its support.