Selected studied localities from Trebinje area, part 1 A locality 1, Vrelo „Vrijeka” (Bijeljani), Dabarsko Polje B locality 5, Vrelo „Pokrivenik” (Muhareva Ljut), Popovo Polje C locality 6, Vrelo „Lukavac” (Zavala) D locality 9, Izvor „Knez” (Trklja) E pumping of interstitial fauna at locality 11, Vrelo „Tučevac” (Mostaći) F locality 13, Vrelo „Polički Studenac” (Crkvina). See also Table 1.