extinction of animation ensues, not a mere suspension, but an annihilation of every power, muscular and vital. As one example of the decisive effects of this fluid, I shall instance the common wasp, a creature so remarkably tenacious of sensation, or so long retaining a muscular power, that it may remain, as every one knows, for days crushed in the window, an apparently dead insect, yet upon pressing the head, the sting will be so protruded as to give a very sensible pain to the finger it should meet with; but upon the prussic acid being injected into this creature as above, when in full vigor, in the course of less than half a minute a loss of vitality ensues, the action of the muscular fibre ceases altogether, and no pressure can incite it again into action. The sudden effect of this liquor is not so generally known as from humanity and expediency might be wished. Who first devised the experiment I am ignorant; but any repetition of means whereby a necessary end can be obtained by the least painful and brief infliction, will hardly be considered as superfluous. This subject naturally introduces the preservation of the creatures after their death, and the young entomologist is not perhaps sensible from experience of the injury some species of insects will effect in the selected specimens of others of this race, and may lament, when too late, the separation of the wings, limbs, and bodies of his collection by these tiny depredators (ptinus fur, acararus destructor). Mr. Waterton’s recipe for preventing this evil, I have used rather extensively and believe it to be a very effectual, and generally an innocuous preservative; but as this gentleman has not given us the exact proportions of his mixture, it may not be useless to observe, that if one part of corrosive sublimate be dissolved in eight parts of good spirit of wine, and the under side of the insect touched with a camel’s- hair pencil, dipped in the liquor, so as to let it lightly pervade every part of the creature, which it readily does, it will, I apprehend, prevent any future injury from insects. A larger portion of the sublimate will leave an unsightly whiteness upon the creature when the specimen becomes dry. The under side of the board, on which the insects are fixed, should be warmed a little by the fire after the application, that the superfluous moisture may fly off, before finally closing the case. If this be omitted, the inner surface of the glass will sometimes become partially obscured by the fume arising from the mixture. The experienced entomologist needs not a notice like this; but the young collector probably will not regard it as unnecessary information, and may be spared by it from both mortification and regret. I have known insects commence their serious operations before the collections of the summer could be arranged in their permanent cases.