Double in situ hybridization of VAChT and VGLUT.Whole mounts with anterior to the left, except for C, F and G, where anterior is up. Whole mount scale bars are 50 μm. In A, C, D, F and H, the dark purple and red staining, respectively, show VAChT and VGLUT expression. In B, E, G and I, the superimposition of brightfield and epifluorescence shows VAChT- and VGLUT-positive neurons. A,B: Lateral views of a 18-hr neurula. C: Dorsal view of the embryo in A and B. D,E: Lateral views of a 24-hr neurula. F,G: Dorsal views of the embryo in D and E. H,I: Lateral views of a 30-hr larva. J,K: Serial confocal fluorescence images of the embryo in H and I. S, somite.