22) Mainly aquatic arthropod usually having a segmented body and chitinous exoskeleton (10) 2) Type of mainly aquatic arthropod usually having a segmented body and chitinous exoskeleton (6) 4) Type of mainly aquatic arthropod usually having a segmented body and chitinous exoskeleton (8) 7) Incapable of being upset or agitated (13) 9) One trouble which leads to another that in turn aggravates the first (7,6) 17) Region of France between Brittany and Picardy (8) 18) Bickering or squabbling (7)