The use of a compound of formula (I), Y is a single bond, C&boxH；O, C&boxH；S or S(O)m where m is 0, 1 or 2； the ring (II) is a 6 membered aromatic ring or is a 5 or 6 membered heteroaromatic ring； Z and Z&prime； are &boxH；C&mdash； or &mdash；N&mdash； provided that both are not N； R1, R2 R3, R3a, R4, R8 and Ra are specified organic groups and n and p are independently 0, 1, 2, 3 or 4； or salts or N-oxides thereof or compositions containing them in controlling insects, acarines, nematodes or molluscs. Novel compounds are also provided.
