Cockroaches have a variety of glands which secrete odorous materials. Certain secretions, produced by tergal or dorsal glands in males, are involved in sexual behavior; the females feed on the secretion from these glands prior to copulating (Roth and Willis, 1954). However, other secretions which are produced by both sexes are ejected or given off when the insect is disturbed; undoubtedly these are defensive weapons that are used against predators. Very few experiments or observations are on record to show how effective these secretions may be in protecting the cockroach. Although the morphology of some of the glands has been described, relatively little is known about the chemistry of their secretions. Many species of Australian cockroaches have been reported to emit "disgusting" odors, though the glands producing these secretions have not been described, nor is the chemistry of the compounds known. _Cosmozosteria lateralis_ exposed two orange-red spots on the abdomen while emitting a pungent odor which deterred a collector from capturing it (Shelford, 1912). Another Australian species, _Platyzosteria castanea_, when disturbed on barren ground tilts forward on the vertex and straddles out the posterior legs, supporting itself in a vertical position on the head and tarsi; in assuming this attitude it will squirt a foetid fluid as a fine spray for a distance of 6 or 7 inches (Shaw, 1914). Spencer (1892) mentions the pungent odor given off by a cockroach which had been accidentally cut in two. Rageau (1956) stated that in the New Hebrides and New Caledonia _Cutilia nitida_ emits, when disturbed, a corrosive liquid with an extremely disagreeable odor.