Abstract

We present GMRT HI observations of two bulgeless spiral galaxies NGC 4701 and NGC 4775. Both galaxies are gas rich, nearly pure disk in morphology and close to face-on. NGC 4701 is a low surface brightness galaxy wih an extended HI gas disk. NGC 4775 is a gas rich dwarf. Our aim is to understand the role of the dark matter halo in limiting the evolution of bulges in these galaxies. As a first step we have mapped the HI gas distributions and derived their HI rotation curves. We present early results of this study and discuss the implications of our results.