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studied the chemical and physical properties of this venom and have found that it does not resemble the venom of any stinging insect previously studied.Venom was collected from major workers taken in the field during the fall and winter. The ants were held by the petiole with a forceps while the tip of the abdomen was stroked with a fine capillary until the sting was everted. Droplets of venom issuing from the tip of the sting were collected in the capillary. The procedure was carried out conveniently under low magnification with a dissecting microscope.The venom is water-insoluble, being less dense than water, in which it disperses as fine milky-colored globules. The absence of ninhydrin-positive reactants indicates it is nonproteolytic. The venom consists of two phases, primarily being composed of an alkaline carrier which suspends fine droplets of a greater density. The alkalinity of the mixture is not due to metal ions. These were determined to be absent by emission spectrographic examination in the Jarrell-Ash 4.8-meter grating spectrograph. The venom is soluble in most organic solvents, but least soluble in ethanol.Ultraviolet spectrophotometric examination of the venom (in ethanol) in a Beckman DU spectrophotometer showed no peaks, absorption being strongest at the lower wavelengths. Infrared examinations (3) were made on a Perkin-Elmer model 21 spectrograph either as a carbon tetrachloride solution or as a film of venom applied directly to the rock salt prism. Only aliphatic C-H stretching was found (3.4 ,u), demonstrating the nonaromatic nature of the venom. A carbonyl group (5.70 it) is present which does not appear to be an open chain, simple ketone (4). Both methyl (7.25 xt) and methylene groups are present as well as a possible ether linkage (8.6 ,j). The C-H/C=O ratio was found to be much higher when the sample contained small amounts of suspended globules. This indicates that the globular component contributes most or all of the carbonyl-containing compound.Insecticidal activity was examined by exposing insects to residues, or by topically applying the venom as obtained from the ants. Samples for residual determinations were prepared as acetone or ethanol solutions. The venom was found to be highly toxic to the fruitfly, Drosophila melanogaster Meig., the housefly, Musca domestica L., a termite, Kaleotermes sp., the boll weevil, Anthonomus grandis Boh., and the rice weevil, Sitophilus oryza (L.). In addition, two species of mites, Tetranychus telarius L. and T. cinnabarinus Boisd., were highly studied the chemical and physical properties of this venom and have found that it does not resemble the venom of any stinging insect previously studied.Venom was collected from major workers taken in the field during the fall and winter. The ants were held by the petiole with a forceps while the tip of the abdomen was stroked with a fine capillary until the sting was everted. Droplets of venom issuing from the tip of the sting were collected in the capillary. The procedure was carried out conveniently under l...

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