Trail and arena marking by caterpillars ofArchips cerasivoranus (lepidoptera: Tortricidae).

The activity ofArchips cerasivoranus caterpillars is largely limited to their colonial silk web and trails. Silk pulled directly from the spinnerets of caterpillars and wound onto paper strips to form artificial trails elicited locomotion from the larvae. Trails made from extracts of silk and silk glands also elicited locomotion. These and other observations reported here indicate that the caterpillars are responsive to a water-soluble pheromone that is a component of the silk strand. Marker pheromones appear not to be secreted from other regions of the body, as has been reported for some other trail-following caterpillars.