Introduction

The role of a secondary bar in shaping the morphology of a galaxy and its possible contribution to bulge formation is an issue which is currently largely unexplored. With more powerful observing techniques beginning to become available, a new look at galaxies which had been classified as unbarred shows that several of them possess a primary bar and some even show secondary bars (Mulchaey et al. 1997). If secondary bars are more prevalent than previously supposed, it is conceivable that they play a role in the secular evolution of galaxies much in the same way as do central mass concentrations (e.g. Hasan & Norman 1990, Sellwood & Moore 1999, Merritt 1998.) Nested gaseous bars have been produced in N-body simulations (Friedli & Martinet 1993; Heller & Shlosman 1994) suggesting that a system of embedded bars may be effective in transporting gas to the galactic center (Pfenniger & Norman 1990, Shlosman et al. 1989), thus influencing galactic evolution. An intuitive insight into the evolutionary process may be gained by examining the stellar dynamics in such systems.