Absence of Natural Volatile Solvents in Cockroach Grease

Abstract

THE wax layer generally present in the epicuticle of insects is important because it reduces loss of water by evaporation^1–3. Except possibly for the cricket⁴, there has not been sufficient knowledge of the chemical composition of the cuticular wax of any insect to formulate with certainty a physico-chemical basis for the physiological action of the wax⁵. A detailed chemical analysis will be published (with Miss M. E. Cox) of the soft grease extracted from the cast skins of cockroaches. Since the preparation of the grease involves recovery from organic solvents, any natural volatile solvents still present in cast skins would not be detected by our techniques. Accordingly, attempts reported here were made to distil volatile compounds from the surface of freshly killed cockroaches.