Velocity plane of the stars in several distant regions. The eight outer panels correspond to heliocentric sectors in the Milky Way disc selected from a ring between 0.5 and 1 kpc from the Sun, in a layer of |Z| < 400 pc and 45deg of amplitude centred at the Galactic longitudes indicated in each panel. The panels are 2D histograms with a bin size of 2 km s^-1, thus, the colour scale indicates the number of stars per 4 (km s^-1)². The middle panel shows the solar neighbourhood sample (defined in Sect. 2.4) for comparison (the same as in Fig. 22, but with a larger bin size). The number of stars is indicated in each panel. We have reversed the horizontal axis V _R to obtain thesame orientation as U (i.e. velocitytowards the Galactic centre).