Occurrence of Gluconic Acid and 2-Hexenal in the Defensive Secretions of Three Species of Eurycotis (Blattaria: Blattidae: Polyzosteriinae)

The main constituents of an acidic, milky secretion from the sternal glands of both adult sexes of Eurycotis decipiens (Kirby) and E. biolleyi Rehn are water, gluconic acid in equilibrium with its lactones, and 2-hexenal. The defensive secretion of E. floridana (Walker), if aqueous, contains gluconic acid as well as 2-hexenal.