1.2 mm continuum maps (contours) obtained with SIMBA at the SEST towards the 11 sources in Table 1 that have an angular resolution of ~24′′. In each panel, the image in the background is the Spitzer-MIPS 24 μm map, which is available for all clumps except for 13039−6108c6, and the circle indicates the ALMA field of view at the frequency of the N₂ H⁺ (3−2) line (~22′′) centred at the coordinates given in Table 1. The first contour and step correspond to the 3σ rms level in the map, with the exception of 16061−5048c1, in which the step is of 6σ rms (see Beltrán et al. 2006 for details). In each panel, the horizontal black bar in the top right corner shows a linear scale of 0.25 pc.