Predator-prey relationships betweenGeocoris punctipes(Say) andHeliothis virescens(F.) were studied in the laboratory by cagingG. punctipesnymphs individually withH. virescenseggs or larvae. The primary objectives of the study were to determine which stages ofH. virescenswere acceptable as prey for each nymphal instar ofG. punctipesand how this predation affected the developmental rate and percent survival of the predator's 5 instars.First-instarG. punctipesnymphs were discovered to be almost exclusively egg predators; the last 4 fed on both eggs and small larvae. All predator stages attained a survival rate of over 96% when they fed on eggs, but when feeding on 1st-instar larvae, survival ranged from 5.6–69.0% for all instars.Predator survival, feeding and development rates decreased as size (or age) of its prey increased; survival rate and feeding rates increased with each successive instar.