We present CO J=3→2 molecular line spectra, and submillimetre photometry at wavelengths λλ377 μm, 811 μm, and 1136 μm for the sources L1551 and IRC+10216. Detailed analysis of the L1551 spectra indicates the presence of strong velocity gradients in the CO emission zones, implying low optical depths and relatively high densities. The central source IRS 5 displays an infrared excess wihich cannot be explained in terms of a single temperature continuum. The emission zone is probably compact with respect to the instrumental beam size at the wavelength of peak emission (λ~50 μm), and may represent an accretion disc responsible for collimation of the high velocity gas. The far-infrared continuum of IRC+10216 has been synthesised by assuming a distribution of optically thin grains whose emissivity varies as εα λ-1, and the CO J=3→2 spectrum for this source supports earlier J=2→1 observations, implying a variable mass-loss rat
