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

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. Small-field peripherally directed angular motion in the frontal visual hemisphere is sufficient to elicit the landing response. Movement from the periphery is not an effective stimulus. Response latency to a large-field peripherally moving striped pattern decreases monotonically with increasing angular velocity. This decrease is consistent with what is known of the dynamics of motion-detecting neurones in other insects. It is suggested that motor mechanisms controlling the landing response, opto-motor turning reactions and flight-power behaviour receive inputs from a common neural motion-detection system.