The Landing Response and Visual Processing in the Milkweed Bug, Oncopeltus Fasciatus

1. The landing response of the milkweed bug Oncopeltus fasciatus consists primarily of extension at one leg joint (femur-tibia) of each of the front four legs upon presentation of the appropriate visual stimulus. 2. Small-field peripherally directed angular motion in the frontal visual hemisphere is sufficient to elicit the landing response. 3. Movement from the periphery is not an effective stimulus. 4. Response latency to a large-field peripherally moving striped pattern decreases monotonically with increasing angular velocity. 5. This decrease is consistent with what is known of the dynamics of motiondetecting neurones in other insects. 6. It is suggested that motor mechanisms controlling the landing response, optomotor turning reactions and flight-power behaviour receive inputs from a common neural motion-detection system.