CO(1−0) spectra at b = 0° at the longitudes observed in [C ii] and [N ii]. The data is taken from the ThrUMMS survey (uncorrected for main beam efficiency) and the inset is a key to the lines of sight observed. Moving towards the CMZ, larger l, CO is not detected until l ~ 358.̊55 (although there is a hint of CO at 358.̊50) at the inner edge of the CMZ, and that only the −207 km s^-1 component is present. The −174 km s^-1 CO component is detected at 358.̊75, the position furthest from the edge of the CMZ and it is considerably weaker there than the −207 km s^-1 component.