Fig. 1. Acquisition curves obtained in classical conditioning experiment with four concentrations of racemic linalool associated with a sucrose reward in H. virescens females (A) and males (B). The proportion (%) of insects showing the PER in each of the 12 conditioning trials is shown. The ISI was 2.5 s. (C,D) The proportion of insects with PER at different points of time (15 and 120 min) after the conditioning trials. The number of individuals included in each group is given above the bars for the 15 min test. An increased percentage of both females and males showed the PER when trained to increasing racemic linalool concentrations.