The relative importance of chemosensory input from the medial vs the
lateral antennular flagellae to the orientation behaviour of the spiny
lobster, Panulirus argus, is examined. The experimental results show
that the lateral filament, specifically the aesthetasc tuft of the
lateral filament, is necessary and sufficient to effect chemotaxis in
this organism. Results further demonstrate a role of lateral filament
input in both tropotactic and klinotactic mechanisms of odour orientation.