Anabaseine, a tobacco alkaloid, is identified as a poison gland product in Aphaenogaster ants, in which it functions as an attractant.

The volatile components of the Dufour's gland secretion of female halictid bees have been examined in 18 Nearctic species belonging toAgapostemon, Augochlora, Augochlorella, Augochloropsis, Dialictus, Evylaeus, Halictus, andLasioglossum. Nine saturated and unsaturated macrocyclic lactones ranging from C18 to C26 have been identified. Four of these compounds, the saturated C26 and the unsaturated C20, C22, and C24 lactones, are new natural products reported for halictine bees. A series of eight esters containing branched C5-alkenols and fatty acids has been identified in several species. The cell linings and pollen ball inAugochlora pura pura contain the same major lactones as the Dufour's gland. A discussion of the significance of the Dufour's gland secretion for apoid systematics and its function in the Halictidae is presented.

The opilionid,Stygnomma spinifera, secretes from a pair of exocrine glands on the cephalothorax between the first and second pair of legs a major volatile component, 2-methyl-5-ethylphenol, and two minor components, 2,3-dimethylphenol and 2,3-dimethyl-5-ethylphenol. These alkylphenols are constituents of a defensive secretion and repel ants, a natural predator of opilionids. The probable significance of this secretion in the biology ofS. spinifera and in the defensive strategies of opilionids in general is discussed.

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