Fig. 7. In choice mating experiments, the females of Chorthippus albomarginatus did not distinguish between conspecific and hybrid males (upper left histogram); in contrast, the females of Ch. oschei mated rather assortatively with conspecific males (upper right histogram); hybrid females obtained from the reciprocal crosses did not distinguish all three types of the males (two lower histograms). The behavioural experiments were conducted during two weeks, 8 hours every day, an equal number of the females and males were placed in one cage during the experiment (number of individuals is shown on the left). Place and date of the collected material: Ch. albomarginatus - Germany, Bavaria, Erlangen, 5.07.2002, Ch. oschei - Hungary, prov. Bekes, Battonya, 16.07.2002.