GFP was observed in the M cell in the L1 and in all Mv cell daughters giving rise to the sex muscles in the L4. The GFP was occasionally maintained in vulval muscle cell nuclei into the adult. GFP expression was also seen in muscles in the head, in vulval and uterine precursors in L2s and L3s, and in several neurons in the head and ventral nerve cord from L2 to adult. There was also GFP expression in the intestine but this was inconsistent. (The images are of strain UL4037 which exhibited broader and stronger expression than UL3567, which had very weak GFP expression).