Distributions of the OCs from Paper I (diamonds), the OCs in the spectroscopic sample (coloured circles), and the OCs in the Dias et al. (2002, version 3.2) catalogue (grey circles) projected onto the Galactic plane, in a linear coordinate system where X increases from the Sun towards the Galactic centre, and Y increases in the direction of Galactic rotation at the location of the Sun. The Galactic centre is located at (X,Y) = (0,0). Metallicity is represented by the colour scale shown in the bar on the right. Solid lines indicate distances from the Galactic centre of 6, 8, and 10 kpc. Three clusters in the spectroscopic sample and one in the photometric sample lie outside the shown X range.