Populations ofMisumenopswere studied in two southern Arizona cotton fields during 1979 and 1980. Spiders were found to be a major component of the general predators (44.2 to 57.6%), andMisumenops celer(Hentz) represented from 45.1 to 75.5% of the spiders collected on a seasonal basis. In general, populations increased steadily through the season unless interrupted by insecticide application. The importance of surrounding vegetation in maintaining populations ofMisumenopsis discussed