Stage 27, day 9; larger magnification (see also Fig. 12); Pfb– Pectoral fin buds; m– mesencephalon; lj– lower jaw; nch – notochord; Ao – aorta dorsalis; Vsi – vena subintestinalis; Vc – vena caudalis; af – anal fin; g – gills; h – heart; lev – left efferent vena vitellina; ys – yolk sac. Scale bar = 2 mm.