1. A comparison of the volatile exocrine secretions of Oecophylla smaragdina with published results on O. longinoda shows the two species are very similar. 2. The contents of Dufour glands of both major and minor workers are closely similar, with undecane the major substance in both castes of both species. 3. The mandibular glands were distinctly different, both between major and minor workers of O. smaragdina and between major workers of the two species. Major workers' mandibular glands contain chiefly hexyl hexanoate, 3-decanone and octyl hexanoate while minor workers contain nerol and 1-nonanol. 4. Males' mandibular glands contain chiefly 3-dodecanone, 3-decanone and 3-decanol, which is very different from the mixture of carboxylic acids in the heads of males of O. longinoda.