FLIERs and other microstructures in planetary nebulae .3.

Long-slit spectroscopic observations along the major axes of four planetary nebulae with interesting jets and FLIERs (Hb 4, IC 4634, NGC 6369, and NGC 7354) have been conducted with the Palomar 5 m telescope. Chemical abundances and physical conditions (n, T) in microstructures were derived along their structural axes. No evidence of conspicuous shock activity or N/O abundance anomalies is seen in most cases, unlike some earlier studies of similar features in other planetary nebulae. Microstructures seem to be a heterogeneous class of structures aside from their low ionization and generally supersonic motions.