Fig. 2. The courtship songs of two natural hybrids in the Chorthippus albomarginatus-group from two localities (a,b - Ukraine, Nikolaev region, Migija, 30.06.99, c,d - Ukraine, Nikolaev region, Koblevo, 8.07.99). In each case two upper traces - leg movements, lower trace - sound recording. (b) and (d) are sections at an expanded time scale of the indicated parts of the songs shown in (a) and (c). Arrows indicate the occurence of A-C elements (a) and A-B elements (c).