Experience long ago taught me that pure and simple desiccation, after a more or less prolonged immersion in alcohol, gives passable results only with scorpions, galeodes, phrynes, and mygales, and consequently with arachnides having thick integuments, while it is entirely unsuccessful with most of the spiders. The abdomen of these shrivels, the characteristic colors disappear in great part, and the animals become unrecognizable. Something else was therefore necessary, and I thought of carbolated glycerine. My process, which I have tried only upon the common species of the country--_Tegenaria domestica_, _Epeira cucurbitina_, _Zilla inclinata_, etc., having furnished me with preparations that were generally satisfactory. I think I shall be doing collectors a service by publishing it in the _Naturaliste_. The specimens should first be deprived of moisture, that is to say, they should be allowed to remain eight or ten days in succession in 50 per cent. alcohol and in pure commercial alcohol. Absolute alcohol is not necessary. After being taken from the alcohol, and allowed to drain, the specimens are immersed in a mixture compound of Pure glycerine 2 volumes, Pure carbolic acid in crystals 1 volume. In this they ought to remain at least a week, but there will be no harm if they are left therein indefinitely, so that the collections of summer may be mounted during winter evenings. What follows is a little more delicate, although very easy. After being removed from the carbolated glycerine, the spiders are placed upon several folds of white filtering paper, and are changed from time to time until the greatest part of the liquid has been absorbed. An insect pin is then passed through the cephalothorax of each individual and is inserted in the support upon which the final desiccation is to take place. This support consists of a piece of sheet cork tacked or glued at the edges to a piece of wood at least one inch in thickness. Upon the cork are placed four or five folds of filtering paper, so that the ventral surface of the pinned spider is in contact with this absorbing surface. For the rest, the legs, palpi, spinnerets, etc., are spread out by means of fine pins, precisely as would be done in the case of coleoptera. [Illustration: SETTING BOARD FOR SPIDERS. A. Absorbent papers. B. Sheet cork. C. Wooden support.] The setting board is put for two or three months in a very dry place under cover from dust. The spiders thus treated will scarcely have changed in appearance, the abdomen of the largest Epeiras will have preserved its form, the hairs will in nowise have become agglutinated, and a person would never suspect that glycerine had performed the role. The forms with a large abdomen require a special precaution; it is necessary to pass the mounting pin through a piece of thin cardboard or of gelatine prolonged behind under the abdomen, because the latter is heavy, and the pedicel that connects it with the cephalothorax easily breaks.