“…(1966) showed that the combined extracts of venom sacs of the American wasps, Polistes annularis Linnaeus, P.fuscatus Lepeletier, and P. exclamans Viereck, also contained three kin ins as had been observed earlier in Vespa vulgaris (MATHIAS and SCHACHTER, 1958). The total kinin activity per wasp produced a response equivalent to 1.5 ~g bradykinin in the rat uterus assay.…”