The Role of the IILR in the Structure of the Central Gaseous Discs

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Recent NICMOS observations of the central regions of nearby barred galaxies, NGC5383, NGC1530 and NGC1667 by Regan, Sheth and Mulchaey (1999), all show, in the unsharp mask map, a pair of distinct trailing spirals which can be followed all the way to the center. This result is in apparent conflict with the density wave theory. In this report, we argue that this difficulty may be removed if we take the self-gravitation of the disc into consideration, or the IILR does not exist in these galaxies.