Abstract
A method is described for observing, photographing, and video-taping the mouthparts of Rhodnius prolixus Stal., a blood-feeding insect, as it feeds on an artificial diet. This method was combined with another for recording the electrical resistance between the haemolymph of a feeding insect and its diet. By using a split-screen television technique simultaneous recordings were made of the changes in electrical resistance and feeding events such as mouthpart movements, salivation, and ingestion. Slow speed and stop-frame playback allowed accurate analysis and correlation of rapid events. The techniques described could be applied to many other types of investigation.