A fixative made of 5 ml of 40% formaldehyde, 2 1/2 ml of glacial acetic acid and 20 gm of chloral hydrate diluted to 100 ml with distilled water is useful for dissecting insects. The advantages of this fixative are that it hardens soft tissues without making them coalesce or become brittle, softens tracheae and the exoskeleton, causes little change in the dimensions of tissues, and it is an excellent preservative. Incisions in the exoskeleton and several sudden releases of vacuum aid in fixation. Details of methods of staining and dissecting are given.