tokens: ≈ x .). For the sample galaxies. the resulting rotation curves predicted by Newton (dashed curves) and by MOND (solid curves) are compared with the observations in Fig. 2 (lower panels), along with the surface density distributions of the baryonic components. It is striking that in several cases (DDO 87, WLM, IC 2574, NGC 3741) the observed structure corresponds quite precisely to that predicted by the baryonic mass distribution in the context of MOND. Note that for WLM, there are a large number of points on the derived rotation curve given by Oh et al. These are certainly not independent, and given their high density obscure the match of the predicted rotation curve to the observations; therefore I have taken only every fourth point in the curve presented here. Figure 2. Each galaxy is represented in two panels. The upper panel is the surface densities of gas (dashed) and stars (dotted) as a function of radius. The lower panel shows the observed rotation curve (points), the Newtonian rotation curve of baryonic components (long dashed curve), and MOND rotation curve. calculated from the Newtonian curve via equation (1) (long dashed curve). The claim here is that these rotation curves are essentially predictions with no free parameters because of the dominance of the gaseous component. But of course there is some contribution from the luminous disc so one might question the extent to which M/L of the disc does vanish as an adjustable parameter. The stellar masses of the sample galaxies (column 6 in Table 1 ) are taken from fitting the colours of the galaxies to population synthesis models in the cases of the seven LT galaxies (Oh et al. 2015 ). For the other five cases they are taken from kinematic considerations (e.g. not exceeding the observed rotation velocity). In half the cases, the implied stellar masses exceed 15 per cent of the total baryonic mass (those objects in which the ratio of gas mass to stellar mass is less than six, column 8). This can certainly affect the shape of the galaxy rotation curves, especially in the inner regions where the stellar disc often contributes more significantly to the baryonic surface density distribution. In Fig. 3 we see the calculated rotation curves for one case where the fraction of stellar mass is fairly typical, DDO 87. The lower dashed curve is the Newtonian rotation curve of baryons excluding the estimated contribution of the visible disc and the upper dashed curve is the same but including the stellar disc with a contribution of 17.5 per cent of the total baryonic mass as given in Table 1 . The upper and lower solid curves are the same but for the MOND rotation curves. While it is obvious that the contribution of the stellar disc provides better agreement with the observations, it is also clear that, with no stellar contribution at all, the rotation curve is qualitatively similar: The overall form of the calculated rotation curves is quite independent of the mass-to-light ratio of the stellar
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