Fig. 5. Spatial and temporal expression of MyoD, myogenin and MyHC mRNA in halibut embryos and larvae with similar numbers of somites. All specimens are dorsal views with the head towards the upper right corner of the picture. Arrowheads indicate the first somite with expression in lateral cells; arrows, the first somite with expression in adaxial cells; dot, asymmetric expression. Scale bar, 0.5 mm for all images.