Red contours: averaged intensity maps of the observed molecular transition indicated in each panel. Contours in a), j) and l) are 10, 20, 30, ... times the rms of the maps, 8, 6 and 9 mK, respectively. In panels m) and n) contours are 20, 23, 26, ... and −3, 3, 6, 9, ... times the rms, 53 mK, respectively. In panels b) and h), k) and p) countours are −3, 3, 6, 9, 12, 15, 20, ... times the rms, 21 mK and 16 mK, respectively. In the rest of the maps contours are −3, 3, 6, 9, 12, 15, 20, 25, 30, 35, ... times the rms, 10 mK. Panel n) shows a fainter component of the ¹³CO molecular line. The beam size of each molecular line is shown at the bottom right corner of each panel. Gray scale: IRAM 30 m MAMBO-II map of the dust continuum emission at 1.2 mm at an angular resolution of 21 arcsec.