It has been known for a number of years that several species of thrips of the genus Frankliniella may be responsible for retardation of growth and malformation of seedling cotton plants. Such damage is characterized by the tightly curled and ragged young leaves. Although this injury has been noted in the Mesilla Valley for some time, it was especially in the Mesilla Valley for some time, it was especially severe in the spring of 1941, due probably to a proparently this insecticide has not been tested for effectiveness against thrips on cotton. During the first week in June plots of a cotton field were sprayed with the following antimony compounds: (1) tartar emetic, 2 pounds; brown sugar, 5 pounds; in 50 gallons of water with 1 pint of Doivax added as a spreader. (2) A proprietary compound, sodium antimony lacto phenolate, 2 pounds; brown sugar, five pounds; in 50 gallons of water. A third plot was left untreated as a check. In 24 hours 20 plants were picked at random from each of the three plots, brought into the laboratory and counts of thrips were made on each plant. A second and third sampling was made 48 hours and 6 days later, respectively. There was no precipitation during the course of the experiment. These data are summarized in table 1.