Spatial distribution of C¹⁸O non-thermal linewidth across NGC 1333 (upper left), IC 348 (upper right), L1448 (lower right) and L1455 (lower left). The grey-scale is SCUBA 850-μm flux density in mJy beam⁻¹ (Hatchell et al. 2005) with contours at 100, 200, 400, 800, 1600 and 3200 mJy beam⁻¹. Circles are positioned at the peak of every SCUBA clump in our catalogue identified using clfind (Curtis & Richer 2010) where there is a 3σ C¹⁸O detection. The circles’ size and colour reflect the linewidth as shown in the key.