The main property of the spiral galaxies dynamics is the flat rotational curve, causing the need of additional mass at the edge of the galactic disk. We show that such a mass is not necessary and it is a consequence of inappropriate assumption on the mass distribution in the theoretical model. Group velocity of the soliton is able to support observed rotational curves with no need of any other but baryonic mass. Peculiar galaxies dynamics with decreasing curves are possible to explain by the same model implying influence on the gala u evolutivno.