  We define new potential-density pairs and examine the impact of the potential
flattening on the vertical velocity ellipsoid tilt, $\delta$. By means of
numerical integrations and analytical calculations, we estimate $\delta$ in a
variety of galactic potentials. We show that at 1 kpc above the Galactic plane
at the solar radius, $\delta$ can differ by 5 degrees, depending on whether the
dark matter halo is flat or spherical. This result excludes the possibility of
an extremely flattened Galactic dark halo.
